What it means
The engine controller cannot read a valid engine serial number from its non-volatile memory, or the stored value does not match the expected pattern. Calibration sets keyed to the serial number cannot be applied.
At a glance
- Usually lights the check-engine light
How it works
The engine controller stores an engine serial number in non-volatile memory and uses it to identify the engine configuration for calibration. This code sets when the stored number is missing, unreadable, or does not match the expected format, so the controller cannot apply the keyed calibration as intended.
Common causes
Most likely first.
- Replacement ECU not programmed at install
- Non-volatile memory corruption
Symptoms
- Check-engine light
- Reduced engine power or limited engine operation
How to diagnose it
- Record freeze-frame data and scan for related controller or programming codes to determine whether this fault appeared after a controller replacement or update.
- Use a compatible scan tool to read the engine serial number stored in the controller and check whether it is blank or invalid.
- Confirm the installed engine and controller identification information matches the vehicle’s records and expected configuration.
- Check the controller’s power and ground connections for faults that could interrupt memory access before assuming the stored data is corrupted.
- If the controller was replaced or its memory is invalid, follow the manufacturer’s programming procedure to enter the correct serial number and apply the compatible calibration.
Common fixes
- Program the correct engine serial number into a replacement controller using the manufacturer’s procedure.
- Restore controller power or ground connections if testing finds an electrical fault.
- Reprogram the controller with the correct compatible calibration if its stored data is corrupted.
- Replace the controller only if its non-volatile memory cannot retain valid data after proper programming.
Can I keep driving?
Driving may be restricted or power may be reduced, so avoid long trips and situations that require brisk acceleration. If the engine runs abnormally or the vehicle limits operation, stop somewhere safe and arrange diagnosis.
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.