P064F
Unauthorized Software or Calibration Detected
The ECU's secure boot or signature check has detected calibration data that is not signed by the manufacturer - typically appears after chip-tuning or unauthorised flash programming. The ECU may run on safe defaults or refuse to start.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: hard
Symptoms
- Check engine light on
- Possible limp mode or no-start
- Multiple follow-up faults across modules
- Reset/relearn may be needed after repair
Common causes
Ordered by how often each turns out to be the cause.
- Unauthorized tuning software flashedCommon
Parts involved
- ECM
P064F is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.