P1AEC

DTC P1AEC-P1AEF

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* 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 Voltage

DTC 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 more than 30 V apart.

DTC P1AEE and P1AEF

The MCM hybrid battery high voltage sensor monitors more than 475 V for more than 0.4 milliseconds.

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 relay contactors.

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 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.

Circuit/System Verification

Important: Repair DTCs P0ABB or P0ABC before performing this diagnostic.

1. Clear the DTC information.
2. Turn the ignition OFF for 1 minute.
3. Turn the ignition ON.
4. Retest for DTCs P1AEC, P1AED,P1AEE and P1AEF.

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. Verification Tests