P06EF
Engine Restart Performance
After a stop-start auto-stop the engine takes longer than calibrated to restart, or restart is missed. Possible causes are weak starter, low battery state of charge, weak crank position signal at low RPM, or a fuel rail that lost prime.
- 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.
- Battery state of charge lowCommon
Parts involved
- Starter Motor
- Battery
- Crankshaft Position Sensor
P06EF 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.