P1381 CADILLAC - Misfire Detected - No Communication with Brake Control Module
Repair Importance Level:
Repair Difficulty Level:
- Repair other codes first
If the P1381 code is set with other codes, repair other codes first and then clear the code.
When is the code detected?
If a loss of communication occurs which causes the Powertrain Control Module (PCM) not to receive rough road information while DTC P0300 is requesting the Malfunction Indicator Lamp (MIL), DTC P1381 will set.
- Engine Light ON (or Service Engine Soon Warning Light)
P1381 Cadillac Description
The Powertrain Control Module (PCM) receives rough road information from the Electronic Brake Control Module (EBCM) on the serial data circuit. 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 EBCM transmits rough road information based on inputs from the wheel speed sensors.