What it means
A control module has detected that the software in the powertrain control module is incompatible with its own software or configuration. Powertrain operation may be affected; the specific effects depend on the vehicle.
At a glance
- Usually lights the warning light of the system that lost communication
- Affects emissions; the car can fail an emissions test
- The engine or gearbox may go into limp mode
How it works
The powertrain control module (PCM) manages engine and, on many vehicles, transmission functions. Other modules compare its software and configuration with the versions they expect; this code sets when a module detects that the PCM’s software or configuration is incompatible, potentially affecting powertrain control and emissions functions.
Common causes
Most likely first.
- Incorrect or incompatible powertrain control module software or calibration
- Module replacement without required programming or configuration
- Incorrect module part number
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
How to diagnose it
- Scan all modules and save freeze-frame data, PCM identification, and communication or configuration codes before clearing anything.
- Note whether the fault began after a PCM replacement, software update, battery-related repair, or other programming work.
- Check whether the PCM communicates consistently and whether its reported part number, software version, and calibration match vehicle-specific service information.
- Inspect PCM connectors, grounds, power feeds, and network wiring for loose, damaged, or corroded connections that could create accompanying communication faults.
- Use the manufacturer’s procedure to verify the PCM calibration and configuration, and program a compatible version if the mismatch is confirmed.
Common fixes
- Repair a loose or corroded PCM connector or wiring connection.
- Complete required PCM configuration or relearn steps using the manufacturer’s procedure.
- Program the PCM with compatible software or calibration.
- Replace an incorrectly specified PCM with the correct compatible unit and program it.
Can I keep driving?
Avoid towing, hard acceleration, and long trips if the engine or transmission is in limp mode, warning lights are on, or powertrain behavior has changed. Continued driving with impaired control can worsen drivability or emissions problems; stop safely if the vehicle loses power or operates unpredictably.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.