Code result

P2A3F

Excessive Time to Enter Alternative Fuel Control

Moderate severity

What it means

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.

Is it safe to drive?

Use caution

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

  • Alt fuel tank pressure low

    high

    One of the most commonly reported causes for this code — check this first.

  • Vaporizer not yet at operating temperature

    medium

    A plausible cause — test and verify before replacing parts.

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