2010 Cadillac Truck Escalade EXT AWD V8-6.2L Page 2994
SDGM
U0100
If any listed DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle (See: Diagnostic Trouble Code Descriptions/Diagnostic
Trouble Code (DTC) List - Vehicle) to diagnose that DTC prior to this diagnostic.
U1885
DTC U1885
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 Descriptor
DTC U1885 00
- Battery Energy Control Module Lost Communication With Hybrid Powertrain Control Module
Diagnostic Fault Information
Circuit/System Description
Modules connected to the serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and
commands are exchanged among the modules. The modules have prerecorded information about what messages are needed to be exchanged on the
serial data circuits, for each virtual network. The messages are supervised and also, some periodic messages are used by the receiver module as an
availability indication of the transmitter module. Each message contains the identification number of the transmitter module.
DTC U1885 will set in the hybrid powertrain control module (HPCM) when the drive motor generator battery control module (BECM) looses
communication with the serial data gateway module (SDGM) on the HSGMLAN serial data bus. The BECM communicates only on the PTLAN
serial data bus while the HPCM communicates on the PTLAN and the HSGMLAN serial data bus.
Conditions for Running the DTC
* The system voltage is between 9-16 volts.
* The vehicle power mode master requires serial data communication to occur from this specific module.
Conditions for Setting the DTC
A supervised periodic message that includes the transmitter module availability has not been received.
Action Taken When the DTC Sets
The modules is never signaled, therefore the specific subsystems will not function.
Conditions for Clearing the DTC
* A current DTC clears when the malfunction is no longer present.
* A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction.
Diagnostic Aids
Different DTCs may set in different modules along with this DTC depending on where the fault occurs and the vehicle operating conditions when
the fault occurs.
Circuit/System Verification
