P068B
ECM or PCM Power Relay De-Energized Performance Too Late
Same as P068A with the relay dropping out later than the calibrated window allows - keeps the ECU powered too long after key-off, drains the battery.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
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.
- Relay contact weldedCommon
Parts involved
- ECM Power Relay
P068B 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.