P1381

DTC P1381

DTC DESCRIPTOR

DTC P1380
Misfire Detected Rough-Road Data Not Available

DTC P1381
Misfire Detected No Communication With Brake Control Module

DIAGNOSTIC FAULT INFORMATION
Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Testing and Inspection

CIRCUIT/SYSTEM DESCRIPTION
The engine control module (ECM) detects engine misfire events by monitoring variations in the crankshaft rotation speed. Wheel speed changes caused by rough road conditions can cause changes in crankshaft speed. By monitoring the wheel speed sensors, the antilock brake system (ABS) can determine if the vehicle is operating on a rough road. If the ABS is detecting a rough road condition severe enough to effect misfire detection, a rough road signal is sent to the ECM on the serial data circuit. If DTC P0300 is set and the rough road information is not available or an ABS malfunction exists, DTC P1380 or P1381 will set.

CONDITIONS FOR RUNNING THE DTC

DTC P1380
- The vehicle speed is more than 0 km/h.
- DTC P1380 runs continuously once the above condition has been met.

DTC P1381
DTC P1381 runs continuously

CONDITIONS FOR SETTING THE DTC

DTC P1380
- The ABS controller sends a message to the ECM indicating that a failure has occurred in the ABS module.
- P0300 is set.

DTC P1381
- Loss of communication between the ECM and the ABS controller.
- P0300 is set.

ACTION TAKEN WHEN THE DTC SETS
- The control module stores the DTC information into memory when the diagnostic runs and fails.
- The malfunction indicator lamp (MIL) will not illuminate.
- The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Failure Records.
- The driver information center, if equipped, may display a message.

CONDITIONS FOR CLEARING THE DTC
- A current DTC Last Test Failed clears when the diagnostic runs and passes.
- A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other non-emission related diagnostic.
- Clear the DTC with a scan tool.

CIRCUIT/SYSTEM VERIFICATION
The scan tool should display antilock brake system (ABS) or communication DTCs. Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code Descriptions

REPAIR INSTRUCTIONS
Always perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests