2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 2787

2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 2787

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)

* Heated Oxygen Sensor Wiring Repairs (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical

Diagnostic Procedures/Wiring Repairs/Heated Oxygen Sensor 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 OFF, open the hood to disable the Auto-Stop function. Refer to Hybrid Modes of Operation Description ( See: Hybrid Drive

Systems/Description and Operation/Hybrid Modes of Operation).

2. Ignition ON, verify the scan tool hood position parameter displays Open.

瀚慖f the hood position does not display Open, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code

Descriptions/Diagnostic Trouble Code (DTC) List - Vehicle) for DTC P254F.

3. Observe the DTC information with a scan tool. Verify there are no other HO2S or fuel trim DTCs set.

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

Trouble Code (DTC) List - Vehicle).

4. Engine idling at operating temperature, observe the appropriate HO2S parameter with a scan tool. Verify the following:

- The HO2S 1 value should vary from below 200 mV to above 800 mV and respond to fueling changes.

- The HO2S 2 value should change greater than 200 mV when the throttle is quickly cycled 3 times from closed to wide open and back to

closed after running the engine at 1,500 RPM for 30 seconds.

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. Verify none of the following conditions exist:

* Lean or rich fuel injectors-Refer to Fuel Injector Diagnosis (CH47976) (See: Powertrain Management/Fuel Delivery and Air

Induction/Fuel Injector/Testing and Inspection)Fuel Injector Diagnosis (J39021 or Scan Tool) (See: Powertrain Management/Fuel

Delivery and Air Induction/Fuel Injector/Testing and Inspection)

* Water intrusion in the HO2S harness connector

* Low or high fuel system pressure-Refer to Fuel System Diagnosis (w/o FPCM) (See: Powertrain Management/Computers and Control

Systems/Testing and Inspection/Component Tests and General Diagnostics)Fuel System Diagnosis (FPCM) (See: Powertrain

Management/Computers and Control Systems/Testing and Inspection/Component Tests and General Diagnostics)

* Fuel that is contaminated-Refer to Alcohol/Contaminants-in-Fuel Diagnosis (Without Special Tool) (See: Powertrain

Management/Computers and Control Systems/Testing and Inspection/Component Tests and General

Diagnostics/Alcohol/Contaminants-in-Fuel Diagnosis (Without Special Tool))Alcohol/Contaminants-in-Fuel Diagnosis (Special Tool) (

See: Powertrain Management/Fuel Delivery and Air Induction/Fuel/Testing and Inspection/Alcohol/Contaminants-in-Fuel Diagnosis

(Special Tool))

* Fuel saturation of the evaporative emission (EVAP) canister

* Exhaust leaks near the HO2S

* Engine vacuum leaks

* Engine oil consumption-Refer to Oil Consumption Diagnosis (See: Engine, Cooling and Exhaust/Engine/Testing and

Inspection/Component Tests and General Diagnostics/Oil Consumption Diagnosis)

* Engine coolant consumption-Refer to Loss of Coolant (See: Engine, Cooling and Exhaust/Cooling System/Testing and

Inspection/Symptom Related Diagnostic Procedures/Loss of Coolant)

瀚慖f you find any of the above conditions, repair as necessary.

2. If all conditions test normal, test or replace the appropriate HO2S.