Code result
P25A4
Fuel Mode Select Switch Circuit
Moderate severity
What it means
General electrical fault on the fuel mode select switch — used on bi-fuel vehicles (CNG/LPG/H2/gasoline) so the driver can pick the active fuel. With the input invalid, the ECM falls back to the default fuel and disables operator-selectable switching.
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
Open or shorted switch wire
highOne of the most commonly reported causes for this code — check this first.
Related help
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