2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 1256
The High Voltage Disabling procedure will perform the following tasks:
* Identify how to disable high voltage.
* Identify how to test for the presence of high voltage.
* Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures
must be followed.
Failure to follow the procedures exactly as written may result in serious injury or death.
1. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling ().
2. Disconnect the X4 harness connector at the drive motor battery control module.
3. Connect the EL-48571 high voltage battery pin out box.
4. Install the high voltage manual disconnect lever. Measure and record each of the 20 battery voltages.
5. Each battery voltage reading should be between 10-19 V.
瀚慖f not within the specified range, replace the drive motor battery assembly.
6. Each battery voltage reading should be within 1.5 V of each other.
瀚慖f not within the specified range, replace the drive motor battery assembly.
7. If all circuits test normal, replace the drive motor generator battery control module.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the repair.
* Drive Motor Generator Battery Replacement and Shipping Preparation ()
* Control Module References (See: Testing and Inspection/Programming and Relearning) for drive motor generator battery control module
replacement, setup and programming.
P0BC1
DTC P0A81 or P0BC1
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 P0A81
- Hybrid Battery Pack Cooling Fan Control Circuit
DTC P0BC1
- Hybrid Battery Pack Cooling Fan Positive Voltage Control Circuit High Voltage
Diagnostic Fault Information
Circuit/System Description
The drive motor generator battery is cooled by a drive motor battery vent fan motor. The battery vent fan motor and battery vent fan relay are
located inside the drive motor generator battery assembly. B+ to the battery vent fan is provided from the battery vent fan relay when the drive
