P2A99 — Alternative Fuel Tank Select Valve C Control Circuit/Open
The control circuit of alternative fuel tank select valve C reports a control circuit/open condition. Tank selection on multi-tank CNG/LPG systems cannot be commanded reliably.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Alt fuel tank select valve c
- Wiring harness
- Afcm
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Open in valve control wire
- Open valve coil
- Pin pushed back out of connector body
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
- Reduced-power or limp mode may occur
Related codes
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.