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P1AE5




DTC P1AE5

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructionsprovides an overview of each diagnostic category.

DTC Descriptor
DTC P1AE5
- Battery Energy Control Module Hybrid Battery Power Off Control Circuit

Diagnostic Fault Information






Typical Scan Tool Data






Circuit/System Description

The drive motor generator battery control module is also referred to as the battery energy control module (BECM). The drive motor generator battery control module will diagnose its own systems and determine when a fault condition is present. Diagnostics and system status is communicated from the drive motor generator battery control module to the hybrid powertrain control module (HPCM) through serial data. The hybrid powertrain control module is the host controller for diagnostic trouble code (DTC) information.

The drive motor generator battery control module receives a pulse width modulated (PWM) signal from the hybrid powertrain control module called the contactor system request circuit command. The drive motor generator battery control module uses this signal to open and close the high voltage contactors.

Conditions for Running the DTC

* The vehicle power mode is RUN.
* Ignition voltage is 9-18 V.

Conditions for Setting the DTC

Contactor system request circuit command signal is less than 25 percent

OR

Contactor system request circuit command signal is between 35 percent and 65 percent

OR

Contactor system request circuit command signal is greater than 75 percent

OR

The frequency of the contactor system request circuit command signal is not between 247 Hz to 253 Hz for 2 out of 3 seconds.

Action Taken When the DTC Sets

DTC P1AE5 is a Type C DTC.

Conditions for Clearing the DTC

DTC P1AE5 is a Type C DTC.

Diagnostic Aids

* The drive motor generator battery control module will set Contactor System Status parameter to OPEN when the Contactor System Request Circuit Command parameter percent duty cycle is 65-75 percent.
* The drive motor generator battery control module will set Contactor System Status parameter to CLOSED when the Contactor System Request Circuit Command parameter percent duty cycle is 25-35 percent.

Reference Information
Schematic Reference

Hybrid Controls Schematics Hybrid Controls Schematics
Connector End View Reference

Component Connector End Views Connector End Views By Name
Electrical Information Reference

* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference

Control Module References Programming and Relearningfor scan tool information

Circuit/System Verification

1. Verify that DTC P2534 is not set.

If the DTC is set, refer to DTC P2534 2ML70 - Automatic Transmission.

2. Ignition ON, observe the scan tool drive motor generator battery control module, Contactor System Request Circuit Command parameter. The reading should be 25-35 percent.
3. Operate the vehicle within the conditions for running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the freeze frame/failure records data.

Circuit/System Testing

Danger: Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed.


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.


Before working on any high voltage system, be sure to wear the following Personal Protection Equipment:


* Safety glasses with appropriate side shields when within 15.24 meters (50 feet) of the vehicle, either indoors or outdoors.

* Certified and up-to-date Class "0" Insulation gloves rated at 1000V with leather protectors.


- Visually and functionally inspect the gloves before use.

- Wear the Insulation gloves at all times when working with the high voltage battery assembly, whether the system is energized or not.


Failure to follow the procedures exactly as written may result in serious injury or death.


1. Ignition OFF, disconnect the X1 harness connector at the drive motor generator power inverter module assembly.
2. Ignition ON, verify that the scan tool Contactor System Request Circuit Command parameter is 100 percent.

If not the specified value, test the control circuit terminal 4 for a short to ground. If the circuit tests normal, replace the Battery Energy Control Module and Bracket Replacement Service and Repair.

3. Install a 3 A fused jumper wire between the control circuit terminal 4 and ground. Verify that the scan tool Contactor System Request Circuit Command parameter is 0 percent.

If not the specified value, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the drive motor generator battery control module.

4. If all circuits test normal, replace the drive motor generator power inverter module assembly.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

Control Module References Programming and Relearningfor drive motor generator battery control module, drive motor generator power inverter control module replacement, setup, and programming