Action Taken When the DTC Sets
* DTCs P0A1B and P0A1C are Type A DTCs.
* The PIM commands the battery energy control module (BECM) to open the high voltage contactor relays.
Conditions for Clearing the DTC
DTCs P0A1B and P0A1C are Type A DTCs.
Reference Information
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (See: Diagnostic Trouble Code Descriptions/Powertrain Diagnostic Trouble Code
(DTC) Type Definitions)
Circuit/System Verification
1. Clear the DTC information.
2. Ignition OFF for 1 minute.
3. Ignition ON.
4. Retest for DTCs P0A1B and P0A1C.
Circuit/System Testing
Program the PIM with the latest software version and recheck for DTCs.
If the DTC resets after programming or if the PIM already contains the latest software version, replace the PIM.
Repair Instructions
Perform the Diagnostic Repair Verification (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning) for PIM replacement, setup, and programming.
P0A1D
DTC P0A1D
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 P0A1D
- Hybrid Powertrain Control Module Internal Performance
Circuit/System Description
The drive motor generator power inverter control module (PIM) contains several microprocessors. This diagnostic applies to internal
microprocessor integrity conditions within the hybrid powertrain control module (HPCM). The HPCM and each Motor Control Module (MCM)
utilize a programmable logic device (PLD) to perform certain input and output functions. At ignition ON, the PLD expects to communicate with the
HPCM and both MCMs. The PLD will communicate to MCM 1 over an internal communication circuit when it has established communications
with the HPCM. MCM 1 will communicate to the engine control module (ECM) over GMLAN if the PLD has not established communication with
the HPCM.
Conditions for Running the DTC
* The control module runs the program to detect an internal fault when the key is ON.
* Ignition voltage is 8-18 volts.
Conditions for Setting the DTC
