2010 Cadillac Truck Escalade RWD V8-6.2L Page 1475
* 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 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 battery energy control module (BECM) also monitors high voltage with several internal sensors. The
BECM high voltage measurement is broadcast over GMLAN.
P1AEC and P1AED
The MCM compares the values in order to verify the hybrid battery high voltage measurement is accurate.
P1AEE and P1AEF
The MCM monitors for high voltage that is greater than the system allows during normal operation.
Conditions for Running the DTC
* The high voltage contactor relays are closed.
* Ignition voltage is 8-18V.
Conditions for Setting the DTC
P1AEC and P1AED
The MCM hybrid battery high voltage sensor measurements are greater than 30V apart.
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 create a voltage surge that may set
