P2A3F
Excessive Time to Enter Alternative Fuel Control
On bi-fuel vehicles, the AFCM cannot transition into alternative fuel control mode within the calibrated time window. Tank pressure low, vaporizer cold, or fuel quality limits the change-over.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: medium
Common causes
Ordered by how often each turns out to be the cause.
- Alt fuel tank pressure lowCommon
- Vaporizer not yet at operating temperaturePossible
Parts involved
- Afcm
- Alt Fuel Tank
- Alt Fuel Vaporizer
P2A3F 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.