Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptor
DTC P1AEC: Drive Motor 1 Control Module Hybrid Battery System VoltageDTC P1AED: Drive Motor 2 Control Module Hybrid Battery System Voltage
DTC P1AEE: Drive Motor 1 Control Module Hybrid Battery System Voltage High
DTC P1AEF: Drive Motor 2 Control Module Hybrid Battery System Voltage High
Circuit/System Description
The drive motor generator power inverter control module (PIM) contains two motor control modules (MCMs). Each MCM measures hybrid battery high voltage with several internal sensors. The MCM compares the values in order to verify the hybrid battery high voltage measurement is accurate.
Conditions for Running the DTC
| • | The high voltage contactor relays are closed. |
| • | Ignition voltage is 8-18 volts. |
Conditions for Setting the DTC
DTC P1AEC and P1AED
The MCM hybrid battery high voltage sensor measurements are greater than 30V apart.
DTC P1AEE and P1AEF
The MCM hybrid battery high voltage sensor monitors greater than 475V.
Action Taken When the DTC Sets
| • | DTCs P1AEC, P1AED, P1AEE and P1AEF 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 P1AEC, P1AED, P1AEE and P1AEF are Type A DTCs.
Diagnostic Aids
DTCs P1AEC and P1AED compare the MCM measured high voltage to the BECM measurement of high voltage which is broadcast over GMLAN. Conditions that cause the BECM to improperly measure high voltage or a failure of the BECM to transmit its high voltage value may set this DTC.
DTCs P1AEE and P1AEF indicate that the high voltage contactor relays may have opened while large current flow was present. Conditions such as loss of BECM power or ground or removal of the high voltage manual disconnect while the vehicle was driving may set this DTC.
Reference Information
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Circuit/System Verification
- Inspect for DTCs P0ABB, P0ABC, P0ABD, or any communication U-code DTCs.
- Clear the DTC information.
- Turn the ignition OFF for 1 minute.
- Turn the ignition ON.
- Retest for DTCs P1AEC, P1AED, P1AEE and P1AEF.
| ⇒ | If the specified DTCs are set, repair them first. Refer to Diagnostic Trouble Code (DTC) List - Vehicle. |
| ⇒ | If the DTC resets, 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 after completing the diagnostic procedure.
Control Module References for PIM replacement, setup, and programming.
