P1380

Circuit Description
This diagnostic DTC is used to determine when the Electronic Brake Control Module (EBCM) has lost the ability to provide rough road data to the Control Module (PCM/VCM) for misfire detection (DTC P0300). When the Control Module detects this condition on the Class 2 serial data circuit, this DTC will be set.

Conditions for Running the DTC
^ The vehicle speed is 1 mph (2 km/h) or more
^ The engine speed is less than 5800 RPM
^ The engine load is less than 89%

Conditions for Setting the DTC
The VCM determines that the ABS system is unable to detect a rough road condition

Action Taken When the DTC Sets
^ The Control Module stores the DTC in history after the first failure but will not illuminate the Malfunction Indicator Lamp (MIL).
^ The Control Module records the operating conditions at the time the diagnostic fails. The Control Module stores the failure information in the scan tools Freeze Frame and/or the Failure Records.

Conditions for Clearing the MIL/DTC
^ A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles.
^ A warm-up cycle occurs when the coolant temperature has risen 22°C (40°F) from the start-up coolant temperature and the Engine Coolant Temperature exceeds 70°C (160°F) during the same ignition cycle.
^ Use the scan tool Clear Information function.

Diagnostic Aids
Check for the following conditions:
An intermittent may be caused by any of the following conditions:
^ A poor connection
^ Rubbed through wire insulation
^ A broken wire inside the insulation

Thoroughly check any circuitry that is suspected of causing the intermittent complaint. Refer to Intermittents and Poor Connections Diagnosis. Symptom Related Diagnostic Procedures

Test Description
The numbers below refer to the step numbers on the Diagnostic Table.
2. This step isolates an open serial data circuit from the EBCM system.