P2A98Alternative Fuel Tank Select Valve B Control Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2A98 appears when the voltage on the control circuit of tank select valve B stays higher than the module allows for the commanded state. A ground-switched valve with an interrupted winding or lead shows this pattern, as does a wire that has picked up battery voltage. The valve will then not move on command, and the system keeps drawing from whichever vessel the resting valve connects. In Westport's two-vessel design with a single pump, that means one tank is used up and the second is never reached, so the engine runs short of gas while the gauge still shows reserve. CARB's heavy-duty rule expects such circuit faults to be detected and stored separately. No manufacturer publishes P2A98. A coil resistance check at the valve plug separates a dead coil from a wiring fault.
- What you may notice
- Malfunction lamp on
- Second vessel never used, gas runs out early
- Gauge shows reserve while power drops
- Likely causes
- LikelyInterrupted winding or lead at valve B
- PossibleControl line of valve B in contact with battery voltage
- RareCorrosion at the valve B connector raising resistance
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €1,200
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.