2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1113

2010 Cadillac Truck SRX AWD V6-2.8L Turbo Page 1113

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the B52 HO2S 2.

2. Ignition ON, verify that the scan tool HO2S 2 voltage parameter is between 350-500 mV.

瀚慖f less than the specified range, test the signal circuit terminal 4 for a short to ground. If the circuit/connections test normal, replace the

K20 ECM.

瀚慖f greater than the specified range, test the signal circuit terminal 4 for a short to voltage. If the circuit/connections test normal, replace the

K20 ECM.

3. Connect a 3 A fused jumper wire between the signal circuit terminal 4 and ground. Verify the scan tool HO2S voltage parameter is less than

60 mV.

瀚慖f greater than the specified range, test the signal circuit for an open/high resistance. If the circuit/connections test normal, replace the

K20 ECM.

4. Connect a 3 A fused jumper wire between the signal circuit terminal 4 and the low reference circuit terminal 3. Verify the scan tool HO2S 2

voltage parameter is less than 60 mV.

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

circuit/connections test normal, replace the K20 ECM.

5. Verify that the following conditions do not exist:

* Lean, rich, or leaking fuel injectors-Refer to Fuel Injector Solenoid Coil Test (LAU) (See: Powertrain Management/Fuel Delivery and

Air Induction/Fuel Injector/Testing and Inspection/Fuel Injector Solenoid Coil Test)Fuel Injector Solenoid Coil Test (LF1, LFW) (See:

Powertrain Management/Fuel Delivery and Air Induction/Fuel Injector/Testing and Inspection/Fuel Injector Solenoid Coil Test).

* A fuel pressure that is too low or too high-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)).

* Fuel that is contaminated-Refer to 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))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)).

* Evidence of water intrusion into the electrical connector of the HO2S

* The HO2S is loose

* Exhaust leaks near the HO2S

* Engine vacuum leaks

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

6. If all circuits/connections test normal, replace the B52 HO2S 2 sensor.

Repair Instructions

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

* Heated Oxygen Sensor Replacement - Sensor 2 (LAU) (See: Powertrain Management/Computers and Control Systems/Oxygen

Sensor/Service and Repair/Heated Oxygen Sensor Replacement - Sensor 2)

* Control Module References (See: Testing and Inspection/Programming and Relearning) for engine control module replacement, setup, and

programming

P0141

DTC P0135 or P0141 (Without LF1)

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.