P1381

DTC P1381 Misfire Detected No EBCM/VCM Serial Data




Circuit Description
This diagnostic will detect a loss of serial communication from the Electronic Brake Control Module(EBCM) to the VCM. This serial communication is essential to distinguish misfire from a rough road condition.

Conditions for Running the DTC
- The vehicle speed is greater than 1 mph (2 km/h).
- The engine speed is less than 5,800 RPM.
- The engine load is less than 89 percent.
- Engine misfire is detected.

Conditions for Setting the DTC
A serial data malfunction is preventing the VCM from receiving rough road detection data.

Action Taken When the DTC Sets
The Malfunction Indicator Lamp (MIL) will not be illuminated. This DTC is stored as a history DTC.

Conditions for Clearing the MIL/DTC
- A history DTC will clear if no fault conditions have been detected for 40 warm-up cycles (coolant temperature has risen 22 °C (40 °F) from the startup 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.

If a repair is necessary, then refer to Wiring Repairs or Connector Repairs.

Steps 1 - 5:

Test Description
Number(s) below refer to the step number(s) on the Diagnostic Table.
2. This step isolates an open serial data circuit from the EBCM system.