What it means
A control module has detected that the software in the vehicle immobilizer control module is incompatible with its own software or configuration. The effect on starting or authorization depends on the vehicle.
How it works
The immobilizer control module checks whether a key is authorized to start the vehicle and exchanges security information with other modules. This code sets when another module finds the immobilizer module’s software or configuration incompatible with its own, which can prevent key authorization or starting.
Common causes
Most likely first.
- Incorrect or incompatible software in the immobilizer control module
- Module replacement without required programming or configuration
- Incorrect module part number
Symptoms
- Starting or key authorization may be affected
- Related warning indicators may illuminate
- A diagnostic scan may show related communication or configuration codes
How to diagnose it
- Scan all modules and save freeze-frame data and related security or communication codes to see which module reported the mismatch.
- Check whether the problem began after an immobilizer, key, or other module was replaced or programmed.
- Use a capable scan tool to read the immobilizer module’s identity, software version, and configuration, then compare them with vehicle-specific service information.
- Inspect the immobilizer module’s connectors and wiring for loose connections, corrosion, or damage that could disrupt its communication.
- Verify the replacement module’s part number and required software compatibility, then carry out the manufacturer’s programming or configuration procedure if indicated.
Common fixes
- Restore a loose or corroded immobilizer-module connection.
- Correct the immobilizer module’s configuration using the manufacturer’s programming procedure.
- Install compatible immobilizer software or calibration.
- Replace an incorrect-part-number module with the correct compatible unit and program it as required.
Can I keep driving?
If the vehicle starts and the key is consistently authorized, limit driving to what is necessary while arranging diagnosis; the fault may leave you unable to restart. If starting or key authorization is unreliable, avoid trips and have the vehicle checked where it is.
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.