P2A99 code meaning
Alternative Fuel Tank Select Valve C Control Circuit/Open
Powertrain system Generic code P2Axx codes Check engine light
What P2A99 means
P2A99 belongs to installations with at least three selectable vessels or supplies and reports an open or otherwise broken control circuit at select valve C. Published designs mostly show two vessels, such as Westport's LNG arrangement with one pump and a valve choosing the tank, or Cespira's pair of compressed-gas supplies; a third valve extends the same principle. With valve C unpowered, its vessel can neither be brought on line nor, depending on the rest position, taken off line, so the selection sequence breaks at that point. Take care not to confuse it with P2A26, the shutoff solenoid on tank C, or with the hydraulic pump select valve. No manufacturer documents P2A99. Check the plug, the lead and the coil of valve C.
P2A99 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 4 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2A99
- Malfunction lamp on
- Third vessel stays full or is never isolated
- Total range reduced
Common causes of P2A99
- Most likelyDisconnected plug or broken lead at select valve C
- PossibleCoil of valve C burnt out
- Less likelyModule output for valve C failed
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Alt fuel tank select valve cWiring harnessAfcm
What each part of P2A99 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| A | Area: hybrid propulsion. |
| 99 | The exact fault in that area. |
What to do next
- Note P2A99 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2A99
What does P2A99 mean?
P2A99 means "Alternative Fuel Tank Select Valve C Control Circuit/Open". P2A99 belongs to installations with at least three selectable vessels or supplies and reports an open or otherwise broken control circuit at select valve C. It is a generic code, so it means the same on every make.
Is it safe to drive with P2A99?
Drive gently and only to a workshop. With P2A99 the car can go into limp mode (reduced power) to protect itself.
Will P2A99 fail an emissions test?
Yes, it can. P2A99 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2A99 to fix?
Difficulty: hard. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will P2A99 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.