P1380

Circuit Description

The PCM uses the rough road information to enhance the misfire diagnostic by distinguishing crankshaft speed variations caused by driving on rough road surfaces from variations caused by true misfires. The Electronic Brake Control Module/Electronic Brake and Traction Control Module (EBCM/EBTCM) transmits rough road information based on inputs from the wheel speed sensors. If the EBCM/EBTCM detects a condition which will not allow it to properly identify rough road situations while a misfire condition is being detected by the PCM, DTC P1380 will be set.

Conditions for Running the DTC

^ Engine load is less than 87%.
^ Engine speed is less than 5000 RPM.
^ Vehicle speed is greater than 10 mph.
^ A misfire DTC is occurring and requesting the MIL to be illuminated.

Conditions for Setting the DTC

The PCM has detected a EBCM/EBTCM rough road sensing error.

Action Taken When the DTC Sets

^ The PCM will not illuminate the Malfunction Indicator Lamp (MIL).
^ The PCM will store conditions which were present when the DTC set as Fail Records data only. This information will not be stored as Freeze Frame data.

Conditions for Clearing the MIL/DTC

^ A history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
^ DTC can be cleared by using a scan tool.

Diagnostic Aids

DTC P1380 set indicates that the Antilock Brake/Traction Control (ABS/TCS) system has detected a malfunction which will not allow the EBCM/EBTCM to transmit correct rough road data to the PCM. The A Diagnostic System Check - ABS should be used to diagnose this condition.