2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 341

* Left front low level audio signal (+) - terminal 15

* Left front low level audio signal (-) - terminal 7

* Right front low level audio signal (+) - terminal 14

* Right front low level audio signal (-) - terminal 6

* Left rear low level audio signal (+) - terminal 13

* Left rear low level audio signal (-) - terminal 5

* Right rear low level audio signal (+) - terminal 12

* Right rear low level audio signal (-) - terminal 4

锟斤拷 If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

radio.

锟斤拷 If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

3. If all circuits test normal, replace the amplifier.

DTC Set By Radio UQA with U42

1. Ignition OFF, disconnect the X3 harness connector at the amplifier.

2. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.

* Left front low level audio signal (+) - terminal 15

* Left front low level audio signal (-) - terminal 7

* Right front low level audio signal (+) - terminal 14

* Right front low level audio signal (-) - terminal 6

锟斤拷 If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

radio.

锟斤拷 If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the radio.

3. Ignition OFF, reconnect the X3 harness connector at the amplifier.

4. Disconnect the X2 harness connector at the rear seat audio (RSA) module.

5. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.

* Left rear low level audio signal (+) - terminal 1

* Left rear low level audio signal (-) - terminal 2

* Right rear low level audio signal (+) - terminal 3

* Right rear low level audio signal (-) - terminal 4

锟斤拷 If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

rear seat audio (RSA) module.

锟斤拷 If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the rear seat audio (RSA)

module.

6. Ignition OFF, reconnect the X2 harness connector at the rear seat audio (RSA) module.

7. Disconnect the X3 harness connector at the amplifier.

8. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.

* Left rear low level audio signal (+) - terminal 13

* Left rear low level audio signal (-) - terminal 5

* Right rear low level audio signal (+) - terminal 12

* Right rear low level audio signal (-) - terminal 4

锟斤拷 If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the

rear seat audio (RSA) module.

锟斤拷 If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the rear seat audio (RSA)

module.

9. If all circuits test normal, replace the amplifier.

DTC Set By Radio UQA with Y91 and U42 or UQS and U42

1. Ignition OFF, disconnect the X3 and X4 harness connectors at the amplifier.

2. Radio ON, test for 5.0-7.5 volts between the appropriate signal circuit terminal listed below and ground.

* Left front low level audio signal (+) - terminal 11 X3

* Left front low level audio signal (-) - terminal 12 X3

* Right front low level audio signal (+) - terminal 3 X3

* Right front low level audio signal (-) - terminal 4 X3

* Left rear low level audio signal (+) - terminal 11 X4

* Left rear low level audio signal (-) - terminal 12 X4

* Right rear low level audio signal (+) - terminal 3 X4

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 707

DTC Descriptor

DTC B3894 5A

- Stop Lamp Switch Circuit Plausibility Failure

Circuit/System Description

The brake switch is hard wired to the fuel pump/trailer brake control module. The body control module (BCM) sends a brake switch status serial

data message to the fuel pump/trailer brake control module. The fuel pump/trailer brake control module compares the states of the brake switch

signal to the serial data message after a master cylinder brake pressure sensor threshold is exceeded. If the brake switch signal and the serial data

message are not in agreement or if the serial data message is not valid, a DTC will set and the trailer brake control system will be disabled.

Conditions for Running the DTC

* Battery voltage is 9.5-17 V.

* The module initialization has taken place.

* The master cylinder brake pressure exceeds threshold

Conditions for Setting the DTC

* The brake switch serial data message is not valid.

* The actual brake switch input to the fuel pump/trailer brake control module, and the serial data information for the brake switch do not match.

Action Taken When the DTC Sets

* The trailer brake control will be disabled for the remainder of the ignition cycle.

* The driver information center (DIC) will display Service Trailer Brake System.

Conditions for Clearing the DTC

* The condition for the DTC is no longer present.

* The fuel pump/trailer brake control module clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.

Reference Information

Schematic Reference

Trailer Brake Control Schematics (See: Brakes and Traction Control/Diagrams/Electrical Diagrams)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Trailer Brake Controls Description and Operation (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Trailer Brake Controls Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

Ignition ON, press the brake pedal. The brake lights should illuminate and the Brake Switch Status parameter should indicate ON.

Circuit/System Testing

1. Verify that DTC B3445, C0277, C0297, or C0890 are not set.

锟斤拷 If any of the DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code

Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle).

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 346

produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone

to move and produce sound. This voltage will vary depending on what type of audio is being listened to, talk or music, and type of music, as well as

the volume setting of the system. Low volume and talk settings will measure around 1V AC and less, where constant music may measure 3V AC and

slightly higher.

Conditions for Running the DTC

The radio is ON.

Conditions for Setting the DTC

Set by Radio

The radio sets a current status for this DTC when a short to ground, short to voltage or an open is detected on any of the speaker channel outputs

from the radio.

Set by Bose Amplifier

The DTC will not set during normal amplifier operation. The vehicle must have the ignition OFF for several hours and the fault must be present

during amplifier power-up.

DTC B1025 01, B1035 01, B1045 01, B1055 01, B1065 01, B1075 01, B1085 01, B1095 01

A short to voltage is detected on the specified (+) or (-) signal circuit

DTC B1025 02, B1035 02, B1045 02, B1055 02, B1065 02, B1075 02, B1085 02, B1095 02

A short to ground is detected on the specified (+) or (-) signal circuit

DTC B1025 04, B1035 04, B1045 04, B1055 04, B1065 04, B1075 04, B1085 04, B1095 04

An open is detected on the specified (+) or (-) signal circuit

Action Taken When the DTC Sets

No sound is present from one or more of the speakers.

Conditions for Clearing the DTC

Set by Radio

The fault condition becomes history if not present for 0.25 seconds.

Set by Bose Amplifier

The fault condition becomes history after the vehicle ignition has been OFF for several hours and then the ignition turns ON.

Diagnostic Aids

Speakers located in the front A-pillar are connected to the same channel as the speaker in the door. A DTC will only set after the amplifier only on

up-level radios.

Reference Information

Schematic Reference

Radio/Navigation System Schematics (See: Accessories and Optional Equipment/Diagrams/Electrical Diagrams/Radio/Navigation System

Schematics)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 439

* Front vertical upward switch terminal A

* Front vertical downward switch terminal K

* Rear vertical upward switch terminal F

* Rear vertical downward switch terminal J

* Horizontal forward switch terminal D

* Horizontal rearward switch terminal C

* Recline forward switch terminal H

* Recline rearward switch terminal G

3. If all circuits test normal, test or replace the seat adjuster switch.

Component Testing

1. Ignition OFF, disconnect the harness connector at the seat adjuster switch.

2. Test for infinite resistance between each seat direction signal terminal listed below and the B+ terminal E with the switch in the open position.

* Front vertical upward switch terminal A

* Front vertical downward switch terminal K

* Rear vertical upward switch terminal F

* Rear vertical downward switch terminal J

* Horizontal forward switch terminal D

* Horizontal rearward switch terminal C

* Recline forward switch terminal H

* Recline rearward switch terminal G

锟斤拷 If not the specified value, replace the seat adjuster switch.

3. Test for less than 1 ohm between each seat direction signal terminal listed below and the B+ terminal E with the switch in the closed position.

* Front vertical upward switch terminal A

* Front vertical downward switch terminal K

* Rear vertical upward switch terminal F

* Rear vertical downward switch terminal J

* Horizontal forward switch terminal D

* Horizontal rearward switch terminal C

* Recline forward switch terminal H

* Recline rearward switch terminal G

锟斤拷 If greater than the specified range, replace the adjuster switch switch.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Power Seat Switch Replacement (with HP2) ()Power Seat Switch Replacement (without HP2) ()

* Control Module References (See: Testing and Inspection/Programming and Relearning) for MSM replacement, setup, and programming

B1815

DTC B1735, B1740, B1745, B1750, B1755, B1760, B1815, or B1820

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptors

DTC B1735 01

- Seat Front Up Switch Circuit Short to Battery

DTC B1740 01

- Seat Front Down Switch Circuit Short to Battery

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 628

Conditions for Running the DTC

Ignition is in the Accessory or Run position.

Conditions for Setting the DTC

The TDM is unable to measure the ignition key transponder value.

Action Taken When the DTC Sets

* Vehicle starting will be disabled.

* The security indicator will be illuminated.

Conditions for Clearing the DTC

* A current DTC will be cleared when the TDM detects a valid transponder value from the ignition key.

* A history DTC will be cleared after 100 malfunction-free ignition cycles or when a scan tool is used to clear DTCs.

Reference Information

Schematic Reference

Immobilizer Schematics (See: Accessories and Optional Equipment/Antitheft and Alarm Systems/Diagrams/Electrical Diagrams/Immobilizer

Schematics)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Immobilizer Description and Operation (See: Accessories and Optional Equipment/Antitheft and Alarm Systems/Description and

Operation/Immobilizer Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Verification

Important: When using this diagnostic, more than one vehicle key is required to ensure proper diagnosis. If more than one key is not

available at the time of service, contact the customer and ask if any other keys can be provided for service. If unavailable, a new second key

can be created.

1. Inspect all available vehicle keys that they are correct vehicle keys.

锟斤拷 If not a correct vehicle key, replace the key.

2. While viewing the scan tool TDM Transponder Key parameter, turn ON the ignition with each of the available vehicle keys. The parameter

should read Present with all available keys.

锟斤拷 If only one key results in the parameter reading Not Present, replace the appropriate key.

锟斤拷 If all available keys result in the parameter reading Not Present, replace the TDM.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Replacing Keys (North America except Canada) (See: Accessories and Optional Equipment/Antitheft and Alarm Systems/Service and

Repair/Replacing Keys (North America Except Canada))

* Control Module References (See: Testing and Inspection/Programming and Relearning) for TDM replacement, setup, and programming

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 58

Diagnostic Aids

* When a harness connector is disconnected, the high control and low control circuits are shorted together by the integral shorting bar. This

should be taken into account when testing for faults on these circuits.

* This DTC usually indicates a poor connection or a wiring malfunction between the SDM and the deployment loop.

Reference Information

Schematic Reference

SIR Schematics (See: Diagrams/Electrical Diagrams/Air Bag Systems)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

SIR System Description and Operation (See: Restraints and Safety Systems/Air Bag Systems/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Special Tools Required

J 38715-A Driver and Passenger SIR Load Tool

Circuit/System Verification

Note: Refer to SIR Service Precautions (See: Restraints and Safety Systems/Air Bag Systems/Service Precautions/Technician Safety Information)

Inspect all terminals for damage or corrosion when disconnecting connectors. Damage or corrosion in the following requires repair or replacement of

the affected component/connector.

* Seat belt pretensioner

* Passenger instrument panel airbag

* Side air bag

* Roof rail airbag

* SDM

* SDM wiring harness connector

Note: The connector and connector position assurance (CPA) may seat independent of each other. Both the connector and CPA should seat with an

audible and/or tactile click. The CPA isolates the shorting-bars within the connector allowing the deployment circuit to operate properly.

If the condition is intermittent or cannot be duplicated, disconnect the connectors and add Nyogel lubricant 760G. This procedure will correct the

high resistance condition due to terminal fretting corrosion.

Observe the scan tool Deployment Loop Resistance parameters while moving the harness near each connector listed below. The reading should stay

consistently between 1.7 and 4.2 ohm without any drop outs or spikes.

* Passenger instrument panel air bag

* Roof rail air bag

* Seat side air bag

* Seat belt pretensioner

* Any inline harness

* SDM

If the reading is erratic while moving the harness, perform the following;

* Inspect each connector terminal for damage or corrosion and repair as necessary.

* Apply Nyogel lubricant 760G to each connector terminal.

* Insure each connector and CPA is correctly seated.

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 66

* Driver seat side airbag terminal 1 and 2

* Passenger seat side airbag terminal 1 and 2

* Driver seat belt retractor pretensioner terminal 1 and 2

* Passenger seat belt retractor pretensioner terminal 1 and 2

7. Verify the scan tool Deployment Loop Resistance parameter is less than 2 ohm.

锟斤拷 If greater than the specified range, test both control circuits terminals for an open/high resistance. If the circuits test normal, replace the

SDM.

8. If all circuits test normal, replace the roof rail air bag, seat side air bag, or seat belt pretensioner.

DTC B0019-B0020

1. Ignition OFF, disconnect the scan tool and disconnect harness connector X200.

2. Wait for 120 seconds and then test for greater than 25 ohm between the appropriate control circuit terminals listed below on the SDM side of

the connector:

* Passenger instrument panel airbag stage 1 terminal 5 and 6 X1

* Passenger instrument panel airbag stage 2 terminal 8 and 7 X1

锟斤拷 If less than the specified range, test for a short between the control circuits, check each connector and CPA to ensure that the shorting bars

are lifted. If the circuits and shorting bars tests normal, replace the SDM.

3. Ignition ON, test for less than 11 V between the control circuit terminals listed below and ground on the SDM side of the connector:

* Control circuit terminal 5 X1

* Control circuit terminal 6 X1

* Control circuit terminal 8 X1

* Control circuit terminal 7 X1

锟斤拷 If greater than the specified range, test the control circuit for a short to voltage. If the circuit tests normal, replace the SDM.

4. Ignition OFF, test for greater than 25 ohm between the control circuit terminals listed below and ground on the SDM side of the connector:

* Control circuit terminal 5 X1

* Control circuit terminal 6 X1

* Control circuit terminal 7 X1

* Control circuit terminal 8 X1

锟斤拷 If less than the specified range, test the control circuit for a short to ground. If the circuit tests normal, replace the SDM.

5. Install a 3 A fused jumper wire between the control circuit terminals listed below.

* Passenger instrument panel airbag stage 1 terminal 5 and 6 X1

* Passenger instrument panel airbag stage 2 terminal 8 and 7 X1

6. Verify the scan tool Deployment Loop Resistance parameter is less than 2 ohm.

锟斤拷 If greater than the specified range, test both control circuits terminals for an open/high resistance. If the circuits test normal, replace the

SDM.

7. Disconnect the passenger instrument panel air bag harness connector.

8. With the appropriate load tool adaptor, connect special tool J 38715-A in place of the air bag.

9. Ignition ON, test for less than 11 V between the control circuit terminals listed below and ground:

* Control circuit terminal A1

* Control circuit terminal A2

* Control circuit terminal B1

* Control circuit terminal B2

锟斤拷 If greater than the specified range, test the control circuit for a short to voltage.

10. Ignition OFF, test for greater than 25 ohm between the control circuit terminals listed below and ground:

* Control circuit terminal A1

* Control circuit terminal A2

* Control circuit terminal B1

* Control circuit terminal B2

锟斤拷 If less than the specified range, test the control circuit for a short to ground.

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 655

DTC B0514 05

- Output Air Temperature Sensor 4 Circuit Short to Battery or Open

DTC B3578 02

- Output Air Temperature Sensor 6 Circuit Short to Ground

DTC B3578 05

- Output Air Temperature Sensor 6 Circuit Short to Battery or Open

DTC B3583 02

- Output Air Temperature Sensor 7 Circuit Short to Ground

DTC B3583 05

- Output Air Temperature Sensor 7 Circuit Short to Battery or Open

Diagnostic Fault Information

Circuit/System Description

Air Temperature Sensors

The air temperature sensors are a 2-wire negative temperature co-efficient thermistor. The vehicle uses the following air temperature sensors:

* Ambient Air Temperature Sensor

* Inside Air Temperature Sensor Assembly

* Upper Left Air Temperature Sensor

* Upper Right Air Temperature Sensor

* Lower Left Air Temperature Sensor

* Lower Right Air Temperature Sensor

* Upper Auxiliary Air Temperature Sensor

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 91

Component Connector End Views

Description and Operation

Running Board Description

Electrical Information Reference

- Circuit Testing

- Connector Repairs

- Testing for Intermittent Conditions and Poor Connections

- Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

1.Verify the left and right side running boards extend and retract when opening and closing the left and right side doors.

If the both running boards do not extend or retract

Perform Circuit/System Testing

锟?If the running boards extend and retract

2.All OK.

Circuit/System Testing

Note:If DTC B051C and/or B051D with symptom bytes 62, 63, or 2A is set, verify that the assist step motor wedge is present and the assist

step motor wedge bolt is tight prior to proceeding with the following diagnostic steps. Refer to Assist Step Motor Replacement for part

location and tightening specifications.

1.Ignition OFF and all vehicle systems OFF. It may take up to 2 minutes for all vehicle systems to power down. Disconnect the harness

connector at the appropriate actuator.

2.Test for less than 10 锟?between the low reference circuit terminal C and ground.

-

If 20 锟?or greater

2.1Ignition OFF, disconnect the harness connector at the Assist Step Control Module.

2.2Test for less than 2 锟?in the low reference circuit end to end.

-If 2 锟?or greater, repair the open/high resistance in the circuit.

-If less than 2 锟? replace the Assist Step Control Module.

锟?If less than 20 锟?

3.Disconnect both Running Board actuators. Ignition ON.

4.Test for 9 - 11 V between the Running Board - Left 10 V reference circuit terminal D and ground while commanding the actuator with the

scan tool.

-

If less than 9 V

4.1Ignition OFF, disconnect the X2 harness connector at the Assist Step Control Module.

4.2Test for infinite resistance between the following 10 V reference circuit terminals and ground.

-X2 Terminal A Running Board - Left

-X2 Terminal B Running Board - Right

-If less than infinite resistance, repair the short to ground on the appropriate circuit.

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 19

The air bag or seat belt retractor pretensioner deployment loop resistance is less than 1.1 ohm for 120 milliseconds.

Action Taken When the DTC Sets

* The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.

* The SDM will store a DTC, however if an event occurs the system will still attempt deployments.

Conditions for Clearing the DTC

* The condition for setting the DTC no longer exists.

* A history DTC will clear once 100 fault-free ignition cycles have occurred.

Diagnostic Aids

* When a harness connector is disconnected, the high control and low control circuits are shorted together by the integral shorting bar. This

should be taken into account when testing for faults on these circuits.

* This DTC usually indicates a poor connection or a wiring malfunction between the SDM and the deployment loop.

Reference Information

Schematic Reference

SIR Schematics (See: Diagrams/Electrical Diagrams/Air Bag Systems)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

SIR System Description and Operation (See: Restraints and Safety Systems/Air Bag Systems/Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Special Tools Required

J 38715-A Driver and Passenger SIR Load Tool

Circuit/System Verification

Note: Refer to SIR Service Precautions (See: Restraints and Safety Systems/Air Bag Systems/Service Precautions/Technician Safety Information)

Inspect all terminals for damage or corrosion when disconnecting connectors. Damage or corrosion in the following requires repair or replacement of

the affected component/connector.

* Seat belt pretensioner

* Passenger instrument panel airbag

* Side air bag

* Roof rail airbag

* SDM

* SDM wiring harness connector

Note: The connector and connector position assurance (CPA) may seat independent of each other. Both the connector and CPA should seat with an

audible and/or tactile click. The CPA isolates the shorting-bars within the connector allowing the deployment circuit to operate properly.

If the condition is intermittent or cannot be duplicated, disconnect the connectors and add Nyogel lubricant 760G. This procedure will correct the

high resistance condition due to terminal fretting corrosion.

Observe the scan tool Deployment Loop Resistance parameters while moving the harness near each connector listed below. The reading should stay

consistently between 1.7 and 4.2 ohm without any drop outs or spikes.

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 578

Reference Information

Schematic Reference

Exterior Lights Schematics (See: Diagrams/Electrical Diagrams/Lighting and Horns/System Diagram/Exterior Lights Schematics)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Exterior Lighting Systems Description and Operation (See: Lighting and Horns/Description and Operation/Exterior Lighting Systems Description

and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the inside rearview mirror.

2. Connect a test lamp between the control circuit terminal 9 and ground.

3. Ignition ON, command the Backup Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the

commanded states.

锟斤拷 If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

锟斤拷 If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the BCM.

4. Ignition OFF, connect the harness connector at the inside rearview mirror. Disconnect the X5 harness connector at the underhood fuse block.

5. Connect a test lamp between the control circuit terminal H8 and ground.

6. Ignition ON, command the Backup Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the

commanded states.

锟斤拷 If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

锟斤拷 If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace

the BCM.

7. If all circuits test normal, replace the underhood fuse block.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Underhood Electrical Center or Junction Block Replacement (See: Maintenance/Fuses and Circuit Breakers/Fuse Block/Service and

Repair/Removal and Replacement/Underhood Electrical Center or Junction Block Replacement)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for BCM, inside rearview mirror, and rearview

camera module replacement, setup, and programming

B2555

DTC B2555

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 679

B3779 61

- Air Flow Control 9 Circuit Actuator Out of Range

B3782 02

- Air Flow Control 10 Feedback Circuit Short to Ground

B3782 04

- Air Flow Control 10 Circuit Actuator Stuck

B3782 05

- Air Flow Control 10 Feedback Circuit Short to Battery or Open

B3782 61

- Air Flow Control 10 Circuit Actuator Out of Range

Circuit/System Description

The HVAC control module controls the HVAC door actuators to regulate the airflow through the HVAC system. Each actuator consists of an

electric motor and a potentiometer. The module supplies a low reference and 5-volt reference source voltage to the potentiometer. The HVAC

control module monitors the voltage drop across the potentiometer on the door position signal circuit. When the actuator shaft rotates, the voltage on

the door position signal circuit changes. The control circuit uses either a 0, 2.5 or 5-volt signal to command the actuator movement. When the

actuator is at rest, the control circuit value is 2.5 volts. A 0 or 5-volt control signal commands the actuator movement in opposite directions.

* B0228 is for the recirculation actuator.

* B0413 is for the drivers air temperature actuator.

* B0423 is for the passenger air temperature actuator.

* B0433 is for the auxiliary air temperature actuator.

* B3779 is for the mode actuator.

* B3782 is for the auxiliary mode actuator.

Conditions for Running the DTC

* Ignition ON.

* The HVAC module is ON.

Conditions for Setting the DTC

The actual door position differs from the commanded door position by more than 4 counts or the HVAC control module detects the door position

signal circuit is less than 3 counts or greater than 253 counts.

Action Taken When the DTC Sets

The control circuit is deactivated for the appropriate actuator.

Conditions for Clearing the DTC

* The DTC becomes history when the HVAC control module no longer detects the condition that set the DTC.

* The history DTC will clear after 100 fault-free ignition cycles.

Reference Information

Schematic Reference

HVAC Schematics (See: Heating and Air Conditioning/Diagrams/Electrical Diagrams/HVAC - Automatic)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

* Air Delivery Description and Operation (See: Heating and Air Conditioning/Description and Operation/HVAC - Automatic/Air Delivery

Description and Operation)

* Air Temperature Description and Operation (See: Heating and Air Conditioning/Description and Operation/HVAC - Automatic/Air

Temperature Description and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 551

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC B2494 02

- Liftgate Handle Switch Circuit Short to Ground

Diagnostic Fault Information

Circuit/System Description

The power liftgate button and exterior liftgate handle switch are parallel circuits and provide a single input to the liftgate module (LGM). The

liftgate switches are supplied voltage and share a common low reference circuit from the LGM. When the switch contacts close, the LGM detects the

voltage drop and commands the liftgate to open or close depending upon the position of the liftgate at the time.

Conditions for Running the DTC

The system voltage is 9-16 volts.

Conditions for Setting the DTC

The Liftgate Open/Close Signal circuit is active for greater than 10 minutes.

Action Taken When the DTC Sets

The liftgate open and close functions from the liftgate switches will be inoperative.

Conditions for Clearing the DTC

* The DTC will be current for as long as the fault is present.

* When the fault is no longer present, the DTC will be a history DTC.

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 480

DTC B1935 0B

- Left Seat Back Heater Circuit Current Above Threshold

DTC B1935 0C

- Left Seat Back Heater Circuit Current Below Threshold

DTC B1935 0D

- Left Seat Back Heater Circuit Resistance Above Threshold

DTC B1935 0E

- Left Seat Back Heater Circuit Resistance Below Threshold

DTC B1935 1F

- Left Seat Back Heater Circuit Intermittent

DTC B2180 04

- Right Seat Back Heater Circuit Open

DTC B2180 0A

- Right Seat Back Heater Circuit Rate of Change Below Threshold

DTC B2180 0B

- Right Seat Back Heater Circuit Current Above Threshold

DTC B2180 0C

- Right Seat Back Heater Circuit Current Below Threshold

DTC B2180 0D

- Right Seat Back Heater Circuit Resistance Above Threshold

DTC B2180 0E

- Right Seat Back Heater Circuit Resistance Below Threshold

DTC B2180 1F

- Right Seat Back Heater Circuit Intermittent

Diagnostic Fault Information

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 441

Driver Seat Schematics ()

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Memory Seats Description and Operation ()

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for Scan Tool Information

Circuit/System Verification

Ignition ON, observe all scan tool Driver Position Module seat switch parameters while pressing and releasing the each seat directional switch. The

reading should change between Inactive and Active.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the seat adjuster switch.

2. Verify the scan tool seat switch parameters listed below are Inactive.

* Front Vertical Upward Switch

* Front Vertical Downward Switch

* Rear Vertical Upward Switch

* Rear Vertical Downward Switch

* Horizontal Forward Switch

* Horizontal Rearward Switch

* Recline Forward Switch

* Recline Rearward Switch

锟斤拷 If not the specified value, test the appropriate signal circuit listed below for a short to voltage. If the circuit tests normal, replace the MSM.

* Front vertical upward switch terminal A

* Front vertical downward switch terminal K

* Rear vertical upward switch terminal F

* Rear vertical downward switch terminal J

* Horizontal forward switch terminal D

* Horizontal rearward switch terminal C

* Recline forward switch terminal H

* Recline rearward switch terminal G

3. If all circuits test normal, test or replace the seat adjuster switch.

Component Testing

1. Ignition OFF, disconnect the harness connector at the seat adjuster switch.

2. Test for infinite resistance between each seat direction signal terminal listed below and the B+ terminal E with the switch in the open position.

* Front vertical upward switch terminal A

* Front vertical downward switch terminal K

* Rear vertical upward switch terminal F

* Rear vertical downward switch terminal J

* Horizontal forward switch terminal D

* Horizontal rearward switch terminal C

* Recline forward switch terminal H

* Recline rearward switch terminal G

锟斤拷 If not the specified value, replace the seat adjuster switch.

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 587

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic System

Check - Vehicle) prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Strategy Based Diagnosis) for an

overview of the diagnostic approach.

* Diagnostic Procedure Instructions (See: Testing and Inspection/Initial Inspection and Diagnostic Overview/Diagnostic Procedure

Instructions) provides an overview of each diagnostic category.

DTC Descriptor

DTC B2600 00

- Daytime Running Lamp Control Circuit

Diagnostic Fault Information

Circuit/System Description

The ambient light sensor is used to monitor outside lighting conditions. The ambient light sensor provides a voltage signal that will vary between 0.2

and 4.9 V depending on outside lighting conditions. The body control module (BCM) provides a 5 V reference signal to the ambient light sensor.

The body control module (BCM) monitors the ambient light sensor signal circuit to determine if outside lighting conditions are correct for either

daytime running lights (DRL) or automatic lamp control (ALC) when the headlamp switch is in the AUTO position. In daylight conditions, the BCM

will command the DRLs ON by applying ground to the DRL resistor via the DRL resistor control circuit. When the BCM applies ground to the DRL

resistor control circuit, the DRL signal circuits to the right and left headlamp assemblies are pulled low. The DRL signal circuits are direct inputs to

the right and left headlamp control modules. When the DRL signal circuits are provided with ground, the right and left headlamp control modules

respond by turning OFF the low beam headlamps and activating the DRLs. Any function or condition that turns the headlamps ON will cancel DRL

operation.

Conditions for Running the DTC

* Battery voltage must be between 9-16 V.

* Headlamp switch in AUTO position.

Conditions for Setting the DTC

The BCM detects a short to voltage in the DRL resistor control circuit.

Action Taken When the DTC Sets

* The Service Headlamp Assembly indicator is commanded ON.

* The BCM will disable the DRL resistor control circuit.

Conditions for Clearing the DTC

* The condition responsible for setting the DTC no longer exists.

* A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.

Reference Information

Schematic Reference

Headlights/Daytime Running Lights (DRL) Schematics (See: Diagrams/Electrical Diagrams/Lighting and Horns/System

Diagram/Headlights/Daytime Running Lights (DRL) Schematics)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Exterior Lighting Systems Description and Operation (See: Lighting and Horns/Description and Operation/Exterior Lighting Systems Description

and Operation)

Electrical Information Reference

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 326

- Audio Output 8 Circuit Short to Ground (RR D-Pillar)

DTC B1095 04

- Audio Output 8 Circuit Open (RR D-Pillar)

Diagnostic Fault Information

Circuit/System Description

Each of the audio output channel circuits (+) and (-), at the radio and audio amplifier have a DC bias voltage that is one half of the battery voltage.

When using a DMM, each of the audio output channel circuits will measure approximately 6.5V DC. The audio being played on the system is

produced by a varying AC voltage that is centered around the DC bias voltage on the same circuit. The AC voltage is what causes the speaker cone

to move and produce sound. This voltage will vary depending on what type of audio is being listened to, talk or music, and type of music, as well as

the volume setting of the system. Low volume and talk settings will measure around 1V AC and less, where constant music may measure 3V AC and

slightly higher.

Conditions for Running the DTC

The radio is ON.

Conditions for Setting the DTC

Set by Radio

The radio sets a current status for this DTC when a short to ground, short to voltage or an open is detected on any of the speaker channel outputs

from the radio.

Set by Bose Amplifier

The DTC will not set during normal amplifier operation. The vehicle must have the ignition OFF for several hours and the fault must be present

during amplifier power-up.

DTC B1025 01, B1035 01, B1045 01, B1055 01, B1065 01, B1075 01, B1085 01, B1095 01

A short to voltage is detected on the specified (+) or (-) signal circuit

DTC B1025 02, B1035 02, B1045 02, B1055 02, B1065 02, B1075 02, B1085 02, B1095 02

A short to ground is detected on the specified (+) or (-) signal circuit

DTC B1025 04, B1035 04, B1045 04, B1055 04, B1065 04, B1075 04, B1085 04, B1095 04

An open is detected on the specified (+) or (-) signal circuit

Action Taken When the DTC Sets

No sound is present from one or more of the speakers.

Conditions for Clearing the DTC

Set by Radio

The fault condition becomes history if not present for 0.25 seconds.

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 605

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information.

Special Tools

* EL-49742 - Battery Voltage (B+) and Ground Source Harness

* J 35616 - GM-Approved Terminal Test Kit

Circuit/System Verification

1. Key ON, engine OFF.

2. Connect a scan tool.

3. Verify that all mode selections of the transfer case shift control switch (TCSCS) match the following parameters in the Data Display feature of

the scan tool:

* Mode Switch Selected

* Transfer Case Position

* The corresponding Mode Indicator Light

Circuit/System Testing

1. Key OFF. Disconnect the X1 connector at the transfer case shift control switch (TCSCS). Install the EL-49742 - harness.

Note: When test probing harness terminals, it is imperative to use the proper test probe from the most current version of the J 35616 - Kit.

Use of an improper test probe may deform the terminal, resulting in intermittent open conditions.

2. Key ON (Ignition C), engine OFF.

3. Using the L-BU probe J 35616-64B, test for 4.8-5.2 V between the 5-volt reference circuit, TCSCS X1 pin 11, and the ground terminal of

EL-49742 - harness, black terminal.

锟斤拷 If the voltage is less than the specified value, test the 5-volt reference circuit for an open/high resistance or short to ground condition. If all

circuits and connections test normal, test the TCCM for proper operation.

锟斤拷 If the voltage is greater than the specified value, test the 5-volt reference circuit for a short to voltage. If all circuits and connections test

normal, test the TCCM for proper operation.

4. Using the L-BU probe J 35616-64B, test for 4.8-5.2 V between the 5-volt reference circuit, TCSCS X1 pin 11, and the switch signal circuit

TCSCS X1 pin 12.

锟斤拷 If the voltage is less than the specified value, test the switch signal circuit for an open/high resistance, short to ground or short together. If

all circuits and connections test normal, test the TCCM for proper operation.

锟斤拷 If the voltage is greater than the specified value, test the switch signal circuit for a short to voltage. If all circuits and connections test

normal, test the TCCM for proper operation.

5. Using the L-BU probe J 35616-64B, test for greater than 50 ohm between the 5-volt reference circuit, TCSCS X1 pin 11, and all other pins of

the TCSCS X1.

锟斤拷 If the resistance is less than the specified value, test the affected circuits for short together condition. If all circuits and connections test

normal, test the TCCM for proper operation.

6. Using the L-BU probe J 35616-64B, test for greater than 50 ohm between the switch signal circuit TCSCS X1 pin 12, and all other pins of the

TCSCS X1.

锟斤拷 If the resistance is less than the specified value, test the affected circuits for short together condition. If all circuits and connections test

normal, test the TCCM for proper operation.

7. Test the TCSCS for proper operation.

Component Testing

TCSCS - Mode Switch Circuit

1. Key OFF. Remove the TCSCS.

2. Using the L-BU probe J 35616-65B, measure the resistance for each of the mode positions of the TCSCS between the 5-volt reference circuit,

TCSCS X1 pin 11, and the switch signal circuit TCSCS X1 pin 12.

锟斤拷 If the resistance is outside the specified ranges, replace the TCSCS.

3. Test the TCCM for proper operation.

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 410

Circuit/System Description

The Driver Door Module (DDM) or Passenger Door Module (PDM) controls the mirror horizontal and vertical motors through the use of

bi-directional motor controls. When the mirror is commanded up and down, voltage or ground is supplied to the mirror vertical motor through the

mirror motor vertical control circuit and voltage or ground is supplied through the mirror motor common control circuit.

Horizontal controls operate in the same manner with the mirror motor horizontal control circuit supplying voltage or ground and the mirror motor

common control circuit suppling voltage or ground to the mirror horizontal motor when the mirror is commanded right and left.

Conditions for Running the DTC

Battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

B1544

An improper voltage level is detected on the driver/passenger mirror motor common control circuit while the mirror is being commanded.

B1600

An improper voltage level is detected on the driver/passenger mirror motor vertical control circuit while the mirror is being commanded.

B1605

An improper voltage level is detected on the driver/passenger mirror motor horizontal control circuit while the mirror is being commanded.

Action Taken When the DTC Sets

Mirror movement is suspended as long as the fault is present.

Conditions for Clearing the DTC

* A current DTC will clear when the fault is no longer present.

* A history DTC will clear after 40 fault free ignition cycles.

Reference Information

Schematic Reference

Outside Rearview Mirror Schematics (See: Body and Frame/Mirrors/Diagrams/Electrical Diagrams/Outside Rearview Mirror Schematics)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Outside Mirror Description and Operation (Heated Mirrors) (See: Body and Frame/Mirrors/Description and Operation/Outside Mirror Description

and Operation (Heated Mirrors))Outside Mirror Description and Operation (Power Mirrors) (See: Body and Frame/Mirrors/Description and

Operation/Outside Mirror Description and Operation (Power Mirrors))

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool References

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

2019 Cadillac Truck Escalade AWD V8-6.2L Diagnostic Instructions Page 590

Schematic Reference

Headlights/Daytime Running Lights (DRL) Schematics (See: Diagrams/Electrical Diagrams/Lighting and Horns/System

Diagram/Headlights/Daytime Running Lights (DRL) Schematics)

Connector End View Reference

Component Connector End Views (See: Diagrams/Connector Views)

Description and Operation

Exterior Lighting Systems Description and Operation (See: Lighting and Horns/Description and Operation/Exterior Lighting Systems Description

and Operation)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit

Testing/Circuit Testing)

* Connector Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic

Procedures/Connector Repairs/Connector Repairs)

* Testing for Intermittent Conditions and Poor Connections (See: Testing and Inspection/Component Tests and General Diagnostics/General

Electrical Diagnostic Procedures/Circuit Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Wiring

Repairs/Wiring Repairs)

Scan Tool Reference

Control Module References (See: Testing and Inspection/Programming and Relearning) for scan tool information

Circuit/System Testing

Warning

The high intensity discharge system produces high voltage and current. To reduce the risk of severe shocks and burns:

* Never open the high intensity discharge system ballast or the arc tube assembly starter.

* Never probe between the high intensity discharge system ballast output connector and the arc tube assembly.

1. Ignition OFF, disconnect the X4 harness connector at the fuse block - underhood.

2. Connect a test lamp between the control circuit terminal H4 and B+.

3. Command the DRLs ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

锟斤拷 If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.

锟斤拷 If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace

the BCM.

4. Ignition OFF, connect the X4 harness connector at the fuse block - underhood. Disconnect the harness connector at the daytime running lamp.

5. Test for less than 5 ohm between the daytime running lamp ground circuit terminal listed below and ground:

* With X88 - Terminal C

* With Z75 and Z88 - Terminal B

锟斤拷 If greater than the specified range, test the ground circuit for an open/high resistance.

6. Connect a test lamp between control circuit terminal A and ground:

7. Command the DRLs ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

锟斤拷 If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the fuse block - underhood.

锟斤拷 If the test lamp is always OFF and the circuit fuse is good, test the control circuit for an open/high resistance. If the circuit tests normal,

test or replace the fuse block - underhood.

锟斤拷 If the test lamp is always OFF and the circuit fuse is open, test the control circuit for a short to ground. If the circuit tests normal, test or

replace the daytime running lamp.

8. If all circuits test normal, test or replace the daytime running lamp.

Repair Instructions

Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.

* Headlamp Replacement (Cadillac Escalade) (See: Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp

Replacement (Cadillac Escalade))Headlamp Replacement (GMC Yukon Two-mode Hybrid) (See: Lighting and Horns/Headlamp/Service

and Repair/Removal and Replacement/Headlamp Replacement (GMC Yukon Two-mode Hybrid))Headlamp Replacement (Yukon) (See:

Lighting and Horns/Headlamp/Service and Repair/Removal and Replacement/Headlamp Replacement (Yukon))Headlamp Replacement