C1285

CIRCUIT DESCRIPTION
The output of the Lateral Accelerometer is measured by the Electronic Brake and Traction Control Module (EBTCM) any time ignition is present. The usable output voltage range for the Lateral Accelerometer is 0.25 - 4.75 volts. The Scan tool will report a zero lateral accelerometer signal of 2.5 volts if no sensor bias (offset) is present and the vehicle is on a flat surface.

CONDITIONS FOR SETTING THE DTC
DTC C1285 can be set any time the ignition is present and the Lateral Accelerometer voltage is less than 0.15 volts or greater than 4.85 volts for approximately 1 second or more.

ACTION TAKEN WHEN THE DTC SETS
Antilock Brake System (ABS) and Traction Control System (TCS) remain enabled, Active Handling is disabled.
^ Indicators that turn on:
- Car Icon (TCS indicator)
^ Messages displayed on the Driver Information Center (DIC):
- Service Active HNDLG

CONDITIONS FOR CLEARING THE DTC
^ Condition for Diagnostic Trouble Code (DTC) is no longer present and Scan tool clear DTC function is used.
^ Fifty ignition cycles have passed with no DTCs detected.

DIAGNOSTIC AIDS
^ It is very important to find out from the driver when the code was set (when the SERVICE ACTIVE HNDLG message was activated). This information may help to duplicate the failure.
^ It is very important that a thorough inspection of the wiring and connectors be performed. Failure to carefully and fully inspect wiring and connectors may result in misdiagnosis, causing part replacement with reappearance of the malfunction.
^ An intermittent malfunction is most likely caused by a poor connection, rubbed through wire insulation, or a wire that is broken inside the insulation. Refer to Testing for Electrical Intermittents in Diagnostic Aids.

TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
24. This step checks for the Electronic Brake and Traction Control Module (EBTCM) pull up voltage.
25. This step checks for the proper Lateral Accelerometer Sensor signal being sent to the EBTCM.
26. This step checks if the EBTCM can properly interpret the Lateral Accelerometer Sensor signal.

Part 1 Of 3:

Part 2 Of 3:

Part 3 Of 3:

DTC C1285 LATERAL ACCELEROMETER SENSOR CIRCUIT MALFUNCTION