2010 Cadillac Truck SRX FWD V6-3.0L Page 1953

2010 Cadillac Truck SRX FWD V6-3.0L Page 1953

* DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.

* The ECM commands the TAC system to operate in a Reduced Engine Power mode.

Conditions for Clearing the DTC

DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.

Diagnostic Aids

* If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, other 5-volt reference circuits may be affected.

* The scan tool 5 volt reference parameter should display between 4.8-5.2 volts.

* A high resistance condition on the accelerator pedal position circuits could cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (LAU) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls Schematics

(LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

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

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

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)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

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

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify DTCs P0697 or P06A3 are not set.

瀚慖f a DTC is set, refer to DTC P0641, P0651, P0697, or P06A3 (LF1) (See: P Code Charts/P0641/ECM) for further diagnosis.

2. Ignition ON, observe the scan tool Accelerator Pedal Position percentage parameter. The scan tool should display 0 percent.

3. Observe the scan tool APP Sensor 1 and 2 Agree/Disagree parameter while performing the following tests:

* Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the

procedure several times.

* Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times.

The APP Sensor 1 and 2 Agree/Disagree parameter should display Agree.

4. Observe the DTC information with a scan tool. DTCs P2122, P2123, P2127, P2128, or P2138 should not set.

5. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the B107 accelerator pedal assembly.

2. Ignition OFF for 1 minute, test for less than 5 ohm between the low reference circuit terminals listed below and ground.

* Low reference circuit terminal 4

* Low reference circuit terminal 5

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2503

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 2503

P2127

The ECM detects that the APP sensor 2 voltage is less than 0.32 V for greater than 0.2 s.

P2128

The ECM detects that the APP sensor 2 voltage is greater than 2.6 V for greater than 0.2 s.

P2138

The voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value for greater than 1 s.

Action Taken When the DTC Sets

* DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

* The control module commands the TAC system to operate in the Reduced Engine Power mode.

* A message center or an indicator displays Reduced Engine Power.

* Under certain conditions the control module commands the engine OFF.

Conditions for Clearing the MIL/DTC

DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

Diagnostic Aids

A high resistance condition on the accelerator pedal sensor circuits could cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

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

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

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)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

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

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0641 or P0651 are not set.

瀚慖f a DTC is set, refer to DTC P0641 or P0651 (ECM) (See: P Code Charts/P0641) for further diagnosis.

2. Observe the scan tool APP Sensor 1 and 2 voltage parameters. Verify both of the APP sensor voltages are between 0.32-4.75 V.

3. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure

several times. DTCs P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

4. Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs

P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

5. Observe the scan tool APP sensor 1 and 2 parameter. The scan tool should display Agree.

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1999

2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1999

P0220, P0222, P0223, P0335, P0336, P0606, P0641, P0651, P1516, P2101, P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2138, and

P2176 are not set.

* When DTC P0315 is set, the engine speed must be more than 1,000 RPM.

* Engine run time is more than 2 crankshaft revolutions.

* The engine speed is between 375-5,600 RPM.

* The ignition voltage is between 9-18 volts.

* The engine coolant temperature (ECT) is between -7 and +130掳C (+19 and +266掳F).

* When the startup ECT is colder than -7掳C (+19掳F), this diagnostic will be delayed until the ECT is warmer than +21掳C (+69掳F).

* The fuel level is more than 10 percent.

* The ECM is not in fuel shut-off, or decel fuel cut-off mode.

* The electronic brake control module (EBCM) and the traction control system (TCS) are not active or detecting rough road.

* An automatic transmission shift with a throttle position more than 95 percent is not occuring.

* The power management is not active.

* Excessive drive wheel slip is not detected.

* The power take-off (PTO) is disabled, where applicable.

* The cylinder deactivation is not in progress, where applicable.

* DTCs P0300-P0308 run continuously when the above conditions are met.

Conditions for Setting the DTC

DTC P0300

The ECM is detecting a crankshaft speed change indicating a random misfire is occuring that exceeds mandated emission level standards or is at

catalytic converter damaging levels.

DTC P0301, P0302, P0303, P0304, P0305, P0306, P0307, or P0308

The ECM is detecting a crankshaft speed change indicating a single cylinder misfire is occuring that exceeds mandated emission level standards or

is at catalytic converter damaging levels.

Action Taken When the DTC Sets

* DTCs P0300-P0308 are Type B DTCs.

* When the MIL is flashing the fuel injector may be disabled for the misfiring cylinder to protect the catalytic converter.

* Depending on the conditions that set the DTC, the engine may go into Open Loop.

Conditions for Clearing the MIL/DTC

* DTCs P0300-P0308 are Type B DTCs.

* The DTC must run and pass under the same operating conditions that were present when the DTC failed.

Diagnostic Aids

* Ensure that each fuel injector is connected to the proper fuel injector harness connector.

* A misfire may only occur when the engine is operating under a load or when the engine is cold.

* A high resistance condition on any ignition control (IC) circuit can cause an engine misfire P0300-P0308 DTC to set without setting an IC

circuit P0351-P0358 DTC.

* This test procedure requires that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test (See:

Starting and Charging/Testing and Inspection/Component Tests and General Diagnostics/Battery Inspection/Test).

* A misfire DTC could be caused by an excessive vibration from sources other than the engine. Inspect the following for possible sources of

vibration:

- A tire or wheel that is out of round or balance

- Variable thickness brake rotors

- An unbalanced drive shaft

- Certain rough road conditions

- A damaged accessory drive component or belt

- A damaged reluctor wheel

- The Crankshaft Position System Variation Learn procedure may need to be performed.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

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

2010 Cadillac CTS Sedan AWD V6-3.0L Page 1835

2010 Cadillac CTS Sedan AWD V6-3.0L Page 1835

* DTCs P2122, P2123, P2127, P2128, and P2138 are type A DTCs.

* The ECM commands the TAC system to operate in a Reduced Engine Power mode.

Conditions for Clearing the DTC

DTCs P2122, P2123, P2127, P2128, and P2138 are type A DTCs.

Diagnostic Aids

* If a shared 5-volt reference circuit is shorted to ground or shorted to a voltage, other 5-volt reference circuits may be affected.

* The scan tool 5 volt reference parameter should display between 4.8-5.2 volts.

* A high resistance condition on the accelerator pedal position circuits could cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (LLT) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls Schematics

(LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

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

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)

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

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

Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

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

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify DTCs P0697 or P06A3 are not set.

瀚慖f a DTC is set, refer to DTC P0641, P0651, P0697, or P06A3 (ECM, LF1) (See: P Code Charts/P0641) for further diagnosis.

2. Ignition ON, observe the scan tool Accelerator Pedal Position percentage parameter. The scan tool should display 0 percent.

3. Observe the scan tool APP Sensor 1 and 2 Agree/Disagree parameter while performing the following tests:

* Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the

procedure several times.

* Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times.

The APP Sensor 1 and 2 Agree/Disagree parameter should display Agree.

4. Observe the DTC information with a scan tool. DTCs P2122, P2123, P2127, P2128, or P2138 should not set.

5. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

conditions that you observed from the Freeze Frame/Failure Records data.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the accelerator pedal assembly.

2. Ignition OFF for 1 minute, test for less than 5 ohm between the low reference circuit terminals listed below and ground.

* Low reference circuit terminal A

* Low reference circuit terminal D

瀚慖f greater than the specified range, test the appropriate low reference circuit for a short to voltage, or an open/high resistance. If the circuit

tests normal, replace the ECM.

2010 Cadillac Truck Escalade RWD V8-6.2L Page 1999

2010 Cadillac Truck Escalade RWD V8-6.2L Page 1999

P0220, P0222, P0223, P0335, P0336, P0606, P0641, P0651, P1516, P2101, P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2138, and

P2176 are not set.

* When DTC P0315 is set, the engine speed must be more than 1,000 RPM.

* Engine run time is more than 2 crankshaft revolutions.

* The engine speed is between 375-5,600 RPM.

* The ignition voltage is between 9-18 volts.

* The engine coolant temperature (ECT) is between -7 and +130掳C (+19 and +266掳F).

* When the startup ECT is colder than -7掳C (+19掳F), this diagnostic will be delayed until the ECT is warmer than +21掳C (+69掳F).

* The fuel level is more than 10 percent.

* The ECM is not in fuel shut-off, or decel fuel cut-off mode.

* The electronic brake control module (EBCM) and the traction control system (TCS) are not active or detecting rough road.

* An automatic transmission shift with a throttle position more than 95 percent is not occuring.

* The power management is not active.

* Excessive drive wheel slip is not detected.

* The power take-off (PTO) is disabled, where applicable.

* The cylinder deactivation is not in progress, where applicable.

* DTCs P0300-P0308 run continuously when the above conditions are met.

Conditions for Setting the DTC

DTC P0300

The ECM is detecting a crankshaft speed change indicating a random misfire is occuring that exceeds mandated emission level standards or is at

catalytic converter damaging levels.

DTC P0301, P0302, P0303, P0304, P0305, P0306, P0307, or P0308

The ECM is detecting a crankshaft speed change indicating a single cylinder misfire is occuring that exceeds mandated emission level standards or

is at catalytic converter damaging levels.

Action Taken When the DTC Sets

* DTCs P0300-P0308 are Type B DTCs.

* When the MIL is flashing the fuel injector may be disabled for the misfiring cylinder to protect the catalytic converter.

* Depending on the conditions that set the DTC, the engine may go into Open Loop.

Conditions for Clearing the MIL/DTC

* DTCs P0300-P0308 are Type B DTCs.

* The DTC must run and pass under the same operating conditions that were present when the DTC failed.

Diagnostic Aids

* Ensure that each fuel injector is connected to the proper fuel injector harness connector.

* A misfire may only occur when the engine is operating under a load or when the engine is cold.

* A high resistance condition on any ignition control (IC) circuit can cause an engine misfire P0300-P0308 DTC to set without setting an IC

circuit P0351-P0358 DTC.

* This test procedure requires that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test (See:

Starting and Charging/Testing and Inspection/Component Tests and General Diagnostics/Battery Inspection/Test).

* A misfire DTC could be caused by an excessive vibration from sources other than the engine. Inspect the following for possible sources of

vibration:

- A tire or wheel that is out of round or balance

- Variable thickness brake rotors

- An unbalanced drive shaft

- Certain rough road conditions

- A damaged accessory drive component or belt

- A damaged reluctor wheel

- The Crankshaft Position System Variation Learn procedure may need to be performed.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

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

2010 Cadillac Truck Escalade AWD V8-6.2L Page 2608

P2127

The ECM detects that the APP sensor 2 voltage is less than 0.32 V for greater than 0.2 s.

P2128

The ECM detects that the APP sensor 2 voltage is greater than 2.6 V for greater than 0.2 s.

P2138

The voltage difference between APP sensor 1 and APP sensor 2 exceeds a predetermined value for greater than 1 s.

Action Taken When the DTC Sets

* DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

* The control module commands the TAC system to operate in the Reduced Engine Power mode.

* A message center or an indicator displays Reduced Engine Power.

* Under certain conditions the control module commands the engine OFF.

Conditions for Clearing the MIL/DTC

DTCs P2120, P2122, P2123, P2125, P2127, P2128, and P2138 are Type A DTCs.

Diagnostic Aids

A high resistance condition on the accelerator pedal sensor circuits could cause a DTC to set.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

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

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

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)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

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

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. Verify that DTC P0641 or P0651 are not set.

锟斤拷If a DTC is set, refer to DTC P0641 or P0651 (ECM) (See: P Code Charts/P0641) for further diagnosis.

2. Observe the scan tool APP Sensor 1 and 2 voltage parameters. Verify both of the APP sensor voltages are between 0.32-4.75 V.

3. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure

several times. DTCs P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

4. Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs

P2120, P2122, P2123, P2125, P2127, P2128, or P2138 should not set.

5. Observe the scan tool APP sensor 1 and 2 parameter. The scan tool should display Agree.

2010 Cadillac Truck Escalade AWD V8-6.2L Page 2087

P0220, P0222, P0223, P0335, P0336, P0606, P0641, P0651, P1516, P2101, P2120, P2122, P2123, P2125, P2127, P2128, P2135, P2138, and

P2176 are not set.

* When DTC P0315 is set, the engine speed must be more than 1,000 RPM.

* Engine run time is more than 2 crankshaft revolutions.

* The engine speed is between 375-5,600 RPM.

* The ignition voltage is between 9-18 volts.

* The engine coolant temperature (ECT) is between -7 and +130锟斤拷C (+19 and +266锟斤拷F).

* When the startup ECT is colder than -7锟斤拷C (+19锟斤拷F), this diagnostic will be delayed until the ECT is warmer than +21锟斤拷C (+69锟斤拷F).

* The fuel level is more than 10 percent.

* The ECM is not in fuel shut-off, or decel fuel cut-off mode.

* The electronic brake control module (EBCM) and the traction control system (TCS) are not active or detecting rough road.

* An automatic transmission shift with a throttle position more than 95 percent is not occuring.

* The power management is not active.

* Excessive drive wheel slip is not detected.

* The power take-off (PTO) is disabled, where applicable.

* The cylinder deactivation is not in progress, where applicable.

* DTCs P0300-P0308 run continuously when the above conditions are met.

Conditions for Setting the DTC

DTC P0300

The ECM is detecting a crankshaft speed change indicating a random misfire is occuring that exceeds mandated emission level standards or is at

catalytic converter damaging levels.

DTC P0301, P0302, P0303, P0304, P0305, P0306, P0307, or P0308

The ECM is detecting a crankshaft speed change indicating a single cylinder misfire is occuring that exceeds mandated emission level standards or

is at catalytic converter damaging levels.

Action Taken When the DTC Sets

* DTCs P0300-P0308 are Type B DTCs.

* When the MIL is flashing the fuel injector may be disabled for the misfiring cylinder to protect the catalytic converter.

* Depending on the conditions that set the DTC, the engine may go into Open Loop.

Conditions for Clearing the MIL/DTC

* DTCs P0300-P0308 are Type B DTCs.

* The DTC must run and pass under the same operating conditions that were present when the DTC failed.

Diagnostic Aids

* Ensure that each fuel injector is connected to the proper fuel injector harness connector.

* A misfire may only occur when the engine is operating under a load or when the engine is cold.

* A high resistance condition on any ignition control (IC) circuit can cause an engine misfire P0300-P0308 DTC to set without setting an IC

circuit P0351-P0358 DTC.

* This test procedure requires that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test (See:

Starting and Charging/Testing and Inspection/Component Tests and General Diagnostics/Battery Inspection/Test).

* A misfire DTC could be caused by an excessive vibration from sources other than the engine. Inspect the following for possible sources of

vibration:

- A tire or wheel that is out of round or balance

- Variable thickness brake rotors

- An unbalanced drive shaft

- Certain rough road conditions

- A damaged accessory drive component or belt

- A damaged reluctor wheel

- The Crankshaft Position System Variation Learn procedure may need to be performed.

Reference Information

Schematic Reference

Engine Controls Schematics (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

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

2010 Cadillac CTS Sedan AWD V6-3.6L Page 1864

2010 Cadillac CTS Sedan AWD V6-3.6L Page 1864

P2127

The APP sensor 2 voltage is less than 0.63 V for greater than 1 s.

P2128

The APP sensor 2 voltage is greater than 4.82 V for greater than 1 s.

P2138

* The ECM detects that the voltage difference between APP sensor 1 and the calculated idle range is greater than 0.25 V, with a released pedal.

* The ECM detects that the voltage difference between APP sensor 2 and the calculated idle range is greater than 0.31 V, with a released pedal.

* The ECM detects that the voltage difference between APP sensor 1 and 2 is greater than 0.31 V with a partially pressed pedal.

* The ECM detects that the voltage difference between APP sensor 1 and 2 is greater than 1.70 V with a fully pressed pedal.

* The ECM detects that the voltage difference between APP sensor 1 and 2 is greater than 0.04 V when APP sensor 1 is greater than 1.17 V.

* Any of the above conditions exist for greater than 1 second, or a cumulative of 10 s.

Action Taken When the DTC Sets

DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.

Conditions for Clearing the DTC

DTCs P2122, P2123, P2127, P2128, and P2138 are Type A DTCs.

Diagnostic Aids

Test the current output of the 5 V reference circuits if you suspect high resistance in the circuit. The current output should be greater than 80 mA

for APP 1 and greater than 50 mA for APP 2.

Reference Information

Schematic Reference

Engine Controls Schematics (LLT) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)Engine Controls Schematics

(LF1) (See: Diagrams/Electrical Diagrams/Powertrain Management/System Diagram)

Connector End View Reference

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

Description and Operation

Throttle Actuator Control (TAC) System Description (See: Powertrain Management/Computers and Control Systems/Description and

Operation/Throttle Actuator Control (TAC) System Description)

Electrical Information Reference

* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/Circuit Testing/Circuit Testing)

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

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

Testing/Testing for Intermittent Conditions and Poor Connections)

* Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/Wiring Repairs/Wiring Repairs)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code

(DTC) Type Definitions)

Scan Tool Reference

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

Circuit/System Verification

1. Ignition ON, observe the DTC information with a scan tool. DTC P0651, P0652, P0653, P0697, P0698, or P0699 should not be set.

瀚慖f a DTC is set, refer to DTC P0641-P0643, P0651-P0653, or P0697-P0699 (ECM, LLT) ( See: P Code Charts/P0641).

2. Observe the scan tool APP Sensor 1 and 2 voltage parameters. Verify both of the APP sensor voltages are between 0.4-4.5 V.

3. Rapidly depress the accelerator pedal from the rest position to the wide open throttle position (WOT) and release pedal. Repeat the procedure

several times. DTCs P2122, P2123, P2127, P2128, or P2138 should not set.

4. Slowly depress the accelerator pedal to WOT and then slowly return the pedal to closed throttle. Repeat the procedure several times. DTCs

P2122, P2123, P2127, P2128, or P2138 should not set.

5. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1840

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1840

DTC P2122, P2123, P2127, P2128, or P2138 (Without LF1, LFW)

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 P2122

- Accelerator Pedal Position (APP) Sensor 1 Circuit Low Voltage

DTC P2123

- Accelerator Pedal Position (APP) Sensor 1 Circuit High Voltage

DTC P2127

- Accelerator Pedal Position (APP) Sensor 2 Circuit Low Voltage

DTC P2128

- Accelerator Pedal Position (APP) Sensor 2 Circuit High Voltage

DTC P2138

- Accelerator Pedal Position (APP) Sensors 1-2 Not Plausible

Diagnostic Fault Information

Typical Scan Tool Data

Circuit/System Description

The accelerator pedal assembly contains two accelerator pedal position (APP) sensors. The APP sensors are mounted in the pedal assembly and are

not serviceable. The APP sensors provide a signal voltage that changes relative to the position of the accelerator pedal. The engine control module

(ECM) supplies a separate 5-volt reference and low reference circuit for each of the APP sensors.

The APP sensor 1 signal voltage increases as the pedal is depressed, from approximately 1.0 volt at rest to approximately 4 volts when fully