2010 Cadillac CTS Sedan AWD V6-3.6L Page 654
If DTC is set, replace the K83 Electric Parking Brake Control Module.
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 Electric Parking Brake Module replacement, setup,
and programming.
C028B
DTC C028B
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 C028B 08
- Park Brake Motor Position Sensor Signal Performance-Signal Invalid
DTC C028B 26
- Park Brake Motor Position Sensor Signal Low Frequency
DTC C028B 29
- Park Brake Motor Position Sensor Signal Too Few Pulses
DTC C028B 2A
- Park Brake Motor Position Sensor Signal Too Many Pulses
Circuit/System Description
The electric parking brake control module has an internal motor, apply actuator, release actuator, and temperature sensor. The electric parking brake
control module also contains the logic for applying and releasing the parking brake when commanded by the electric parking brake switch. When
the electric parking brake control module receives a signal from the switch the internal circuit board temperature is checked to verify it is within
operating range before the control module performs the requested operation. The electric parking brake module also contains an internal park brake
motor position sensor which monitors the internal park brake motor position.
The Park Brake Motor Position Sensor is an internal sensor to the electric park brake controller, this sensor is used to monitor internal park brake
motor position.
Conditions for Running the DTC
Ignition OFF, ACCESSORY, or RUN mode.
Conditions for Setting the DTC
The electric parking brake module detects an internal motor position sensor signal malfunction.
Action Taken When the DTC Sets
* The electric parking brake is disabled, one release allowed.
* A DIC message and/or a warning indicator may be displayed.
Conditions for Clearing the DTC
* The electric parking brake module clears the history DTC when a current DTC is not detected in 40 ignition cycles.
* Calibrate the electric parking brake module.
