P2A25
- Powertrain
- Manufacturer-specific
- Emissions
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Driving may cause further damage or leave you stranded. Arrange service promptly rather than waiting.
Alternative Fuel Tank Shutoff Valve B Control Circuit High
This code is in our catalogue but has not yet been through editorial review, so the guidance below is limited to what our structured data supports. We publish deeper diagnostic content only after a code has been reviewed — here is why.
The control circuit of alternative fuel tank shutoff valve B reports a control circuit high condition. Tank isolation cannot be commanded as expected on multi-tank CNG/LPG systems.
A trouble code records what a control module measured. It does not identify which part failed. Test before replacing anything.
- Safe to drive
- Driving may cause further damage or leave you stranded. Arrange service promptly rather than waiting.
- Urgency
- Get it looked at now
- Will it pass emissions
- No
- Check engine light
- Solid
| # | Cause | How often | Component |
|---|---|---|---|
| 1 | Control wire shorted to B+ | Very common | — |
| 2 | Open valve coil | Common | — |
| 3 | Connector pins corroded - high contact resistance | Occasional | — |
Ordering reflects how often each cause is responsible in general, not a probability for your vehicle. Confirm by testing.
- Alt Fuel Tank Shutoff Valve B
- Wiring Harness
- AFCM
- Definition
- Generic code set (SAE J2012 / ISO 15031-6) via the OBDexopen database, dedicated to the public domain under CC0-1.0.
- Diagnostic guidance
- Written and reviewed in-house. See our editorial policy.
- Review status
- Awaiting review
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