2010 Cadillac Truck Escalade RWD V8-6.0L Hybrid Page 974
C121D
DTC C0552 or C121D
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) provide an overview of each diagnostic category.
DTC Descriptors
DTC C0552 00
- Improper Shutdown
DTC C121D
- Improper Shutdown
Circuit/System Description
The electronic brake control module(EBCM) monitors the number of Key On and Key Off cycles. When it detects that a Key Off cycle was
incomplete or non-existent this fault will set. This means the fault reports a problem that occurred at the end of the previous ignition cycle. If this
occurs during an EBCM service operation, any calibrations or offsets learned during that service operation may not be properly stored in memory.
Conditions for Running the DTC
* Ignition ON.
* The ignition voltage is greater than 10 volts.
* The EBCM is initializing.
Conditions for Setting the DTC
A Key Off cycle was interrupted before completion, or power was removed from the module with the key in the ON position, vehicle moving and
brake is applied.
Action Taken When the DTC Sets
* The EBCM disables the antilock brake system (ABS), traction control and the vehicle stability enhancement system (VSES) for the duration
of the ignition cycle.
* A DIC message and/or a warning indicator may be displayed.
Conditions for Clearing the DTC
* The condition for the DTC is no longer present.
* The EBCM clears the history DTC when a current DTC is not detected in 40 consecutive drive cycles.
Diagnostic Aids
This DTC can set if battery voltage drops below 8 volts with ignition ON.
Reference Information
Schematic Reference
Antilock Brake System Schematics (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Diagrams/Electrical Diagrams)
Connector End View Reference
Component Connector End Views (See: Diagrams/Connector Views)
Description and Operation
ABS Description and Operation (See: Brakes and Traction Control/Antilock Brakes / Traction Control Systems/Description and Operation/ABS
Description and Operation)
Electrical Information Reference
* Circuit Testing (See: Testing and Inspection/Component Tests and General Diagnostics/General Electrical Diagnostic Procedures/Circuit
Testing/Circuit Testing)
