P24FA
Exhaust Aftertreatment Fuel Air Purge Valve Control Circuit Low
The control circuit of the aftertreatment purge valve reads stuck low — usually a short to ground or a failed low-side driver. The valve is energised continuously when it should be off, or the diagnostic feedback voltage is pulled below threshold.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Control wire shorted to groundCommon
- Failed low-side driver stuck onPossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Aftertreatment Purge Valve
- Solenoid Driver
P24FA 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.