2010 Cadillac Truck SRX FWD V6-3.0L Page 2001

2010 Cadillac Truck SRX FWD V6-3.0L Page 2001

P0443, P0458, P0459, P0461, P0462, P0463, P2068 P2088, P2089, P2090, P2091, P2092, P2093, P2094, and P2095 must run and pass.

* The engine speed is between 480-1,001 RPM.

* The engine load is between 7-32 %.

* The MAF is between 1-8 g/s.

* The fuel system is in Closed Loop.

* The engine is not in decel fuel cut-off.

* The long term fuel trim is active.

* The engine coolant temperature (ECT) is greater than 60掳C (140掳F).

* The intake air temperature (IAT) is less than 61掳C (142掳F).

* The evaporative emission (EVAP) canister purge solenoid valve is not enabled.

* The fuel level is greater than 12 %.

* The amount of air flow into the engine is greater than 7,000 g.

* DTCs P2187 and P2189 run continuously when the above conditions are met.

Conditions for Setting the DTC

P2177

The Total Fuel Trim Avg. is greater than 23 % for 4 s or for a cumulative of 30 s.

P2187

The Total Fuel Trim Avg. is greater than 40 %, or the long term fuel trim Idle/Decel is greater than 6 %. Either condition exists for 4 s or for a

cumulative of 30 s.

Action Taken When the DTC Sets

DTCs P2177 and P2187 are Type B DTCs.

Conditions for Clearing the MIL/DTC

DTCs P2177 and P2187 are Type B DTCs.

Diagnostic Aids

* A fuel system delivery condition causes this DTC to set. Thoroughly inspect all items that cause a lean condition. Refer to Fuel System

Diagnosis (LF1 China) (See: Powertrain Management/Fuel Delivery and Air Induction/Fuel Pump/Testing and Inspection/Fuel System

Diagnosis (China))Fuel System Diagnosis (LF1 Except China) (See: Powertrain Management/Fuel Delivery and Air Induction/Fuel

Pump/Testing and Inspection/Fuel System Diagnosis (Except China))Fuel System Diagnosis (LAU China) (See: Powertrain

Management/Fuel Delivery and Air Induction/Fuel Pump/Testing and Inspection/Fuel System Diagnosis (China))Fuel System Diagnosis

(LAU Except China) (See: Powertrain Management/Fuel Delivery and Air Induction/Fuel Pump/Testing and Inspection/Fuel System

Diagnosis (Except China)).

* Any un-metered air into the engine causes this DTC to set. Thoroughly inspect all areas of the engine for vacuum leaks.

* A MAF sensor condition can cause this DTC without setting a MAF DTC. If there is a MAF sensor condition, the MAF sensor parameters

will appear to be within range.

* Inspect the air filter for being the correct one for this application. Make sure that the engine oil fill cap is in place and that it is tight. Verify

that the engine oil dip stick is fully seated.

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)

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

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1871

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1871

* DTC P0461, P0462, P0463, P2066, P2067, or P2068 is not set.

* The engine is operating.

* The ignition voltage is greater than 10 V.

* The rear HO2S are at operating temperature for greater than 10 s.

* The fuel injectors are enabled.

* The long term fuel control is enabled.

* The mass air flow sensor is greater than 10 g/s.

* The MAF sensor is between 6-33 g/s for greater than 3 s during the intrusive test.

* The accumulated air flow into the engine is greater than 15 g during the fuel cut-off event.

* DTC P2271 runs continuously when the above conditions are met.

Conditions for Setting the DTC

The ECM detects that the rear HO2S voltage is greater than 650 mV for greater than 100 s, then an intrusive test is performed. The ECM will lean

the fuel mixture up to -7 % and then wait for 10 s at -7 %. If the ECM detects that the HO2S voltage is still greater than 650 mV, the ECM then

tests the HO2S at the next decel fuel cut-off. If the ECM detects the HO2S voltage is greater than 200 mV after 4 s or for a cumulative of 30 s in

decel fuel cut-off, the DTC sets.

Action Taken when the DTC Sets

DTC P2271 is a Type B DTC.

Conditions for Clearing the MIL/DTC

DTC P2271 is a Type B DTC.

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)

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 P0137, P0138, or P0140 is not set.

瀚慖f any of the listed DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code

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

2. Operate the engine above 1,200 RPM for 30 s, observe the HO2S 2 voltage parameter. The reading should fluctuate above and below the

range of 350-550 mV.

3. 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. Engine operating, move the related HO2S harness between the B52 HO2S harness connector and the K20 ECM while monitoring the HO2S

2 voltage parameter. Verify that the HO2S 2 parameter does not change abruptly while moving the related harnesses.

2010 Cadillac Truck Escalade AWD V8-6.2L Page 2191

P0462

DTC P0462

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 P0462

- Fuel Level Sensor 1 Low Voltage

Diagnostic Fault Information

Circuit/System Description

The fuel level sensor changes resistance in response to the fuel level. The engine control module (ECM) monitors the signal circuit of the fuel level

sensor and the type of fuel in order to determine the fuel level. For regular unleaded fuel the ECM monitors a constant signal. When the vehicle has

approximately 20% or greater ethanol for E85 fuel applications, the ECM controls a pulse cycle signal where it monitors the signal and calculates

the fuel level percentage only during the on pulse of approximately 100 ms.

When the fuel tank is full, the sensor resistance is low and the ECM senses a low signal voltage. When the fuel tank is empty, the sensor resistance

is high and the ECM senses a high signal voltage. The ECM uses the signal circuit of the fuel level sensor in order to calculate the percentage of

remaining fuel in the tank. The ECM sends the fuel level percentage via the serial data circuit to the instrument cluster in order to control the fuel

gauge.

Conditions for Running the DTC

* The ignition is ON, with the engine running.

* The system voltage is between 11-18 V.

Conditions for Setting the DTC

* The sender output is less than 0.5 V.

* The above condition is present for greater than 30 seconds.

Action Taken When the DTC Sets

* The fuel gauge defaults to empty.

* The low fuel indicator illuminates.

* The ECM records the operating conditions at the time that the diagnostic test fails. The ECM displays the failure information in the Failure

Records on the scan tool.

Conditions for Clearing the DTC

* The DTC becomes history when the conditions for setting the DTC are no longer present.

* The history DTC clears after 40 malfunction-free warm-up cycles.

Diagnostic Aids

A defective fuel level sensor most likely will not set DTC P0462. The sensor has a 500 ohm default resistor that will prevent it from meeting the

code setting criteria of this DTC. Look for problems in the wiring and in the inline and harness connectors at the sensor and ECM.