2010 Cadillac Truck Escalade/ESV RWD V8-6.2L Page 1796
Note: All modules must be powered down or misdiagnosis may result.
1. Ignition OFF, disconnect the harness connector at the appropriate B52 HO2S.
2. Ignition OFF, all vehicle systems OFF, this may take up to 2 minutes, test for less than 5 ohm between the low reference circuit terminal A
and ground.
瀚慖f greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the K20
ECM.
3. Ignition ON, verify the appropriate scan tool B52 HO2S parameter is approximately 450 mV.
瀚慖f less than the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the K20 ECM.
瀚慖f greater than the specified value, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K20 ECM.
4. Ignition ON, install a 3 A fused jumper wire between the signal circuit terminal B and ground. Verify the appropriate scan tool B52 HO2S
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 tests normal, replace the K20 ECM.
5. If all circuits test normal, replace the appropriate B52 HO2S.
Repair Instructions
Caution: Refer to Heated Oxygen Sensor Resistance Learn Reset Caution (See: Powertrain Management/Computers and Control
Systems/Oxygen Sensor/Service Precautions/Heated Oxygen Sensor Resistance Learn Reset Caution).
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
* Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 (1500 Series) (See: Powertrain Management/Computers and Control
Systems/Oxygen Sensor/Service and Repair)Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 (2500 Series) (See: Powertrain
Management/Computers and Control Systems/Oxygen Sensor/Service and Repair)
* Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 (1500 Series) (See: Powertrain Management/Computers and Control
Systems/Oxygen Sensor/Service and Repair)Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 (2500 Series) (See: Powertrain
Management/Computers and Control Systems/Oxygen Sensor/Service and Repair)
* Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 (1500 Series) (See: Powertrain Management/Computers and Control
Systems/Oxygen Sensor/Service and Repair)Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 (2500 Series) (See: Powertrain
Management/Computers and Control Systems/Oxygen Sensor/Service and Repair)
* Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 (1500 Series) (See: Powertrain Management/Computers and Control
Systems/Oxygen Sensor/Service and Repair)Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 (2500 Series) (See: Powertrain
Management/Computers and Control Systems/Oxygen Sensor/Service and Repair)
* Control Module References (See: Testing and Inspection/Programming and Relearning) for ECM replacement, setup, and programming
P0135
DTC P0030, P0036, P0050, P0053, P0054, P0056, P0059, P0060, P0135, P0141, P0155, or P0161
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 P0030
- HO2S Heater Control Circuit Bank 1 Sensor 1
DTC P0036
- HO2S Heater Control Circuit Bank 1 Sensor 2
DTC P0050
- HO2S Heater Control Circuit Bank 2 Sensor 1
DTC P0053
- HO2S Heater Resistance Bank 1 Sensor 1
