2010 Cadillac Truck Escalade ESV AWD V8-6.2L Page 1602
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.
锟斤拷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 ().
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.
锟斤拷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 (See: Verification Tests) after completing the diagnostic procedure.
Control Module References (See: Testing and Inspection/Programming and Relearning) for drive motor generator battery control module, drive
motor generator power inverter control module replacement, setup, and programming
P1AE6
DTC P1AE6 or P1AE7
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 P1AE6
- Battery Energy Control Module Hybrid Battery Voltage Isolation Sensor Circuit
DTC P1AE7
- Battery Energy Control Module Hybrid Battery Voltage System Isolation Lost
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 vehicle is equipped with a high voltage isolation monitor feature. The purpose of the high voltage isolation circuit is to test the resistance
between the high voltage positive and negative direct current (DC) bus and chassis ground. The drive motor generator battery control module only
runs this test when the ignition transitions from ON to OFF and the high voltage contactor relays have opened. The drive motor generator battery
control module has an internal isolation sensor that measures the resistance between the high voltage DC positive and negative bus and chassis
ground. The drive motor generator battery control module runs an internal self check of this sensor circuit. If the internal self check fails DTC
P1AE6 will set. The drive motor generator battery control module sends an AC signal over the DC bus and monitors its amplitude. A low amplitude
or collapsed return signal indicates a loss of resistance to chassis ground and a loss of isolation will be indicated by the drive motor generator
battery control module. This DTC indicates that the fault is in the drive motor generator battery. Because this diagnostic runs after system power
down, the diagnostic status does not get reported until the next key cycle.
Conditions for Running the DTC
* Ignition voltage is 9-18 V.
* The ignition switch transitions from ON to OFF.
* High voltage contactor transitions to open.
