P2A29 code meaning
Alternative Fuel Tank Shutoff Valve C Control Circuit High
Powertrain system Generic code P2Axx codes Check engine light
What P2A29 means
P2A29 sets when the drive circuit of shutoff valve C sits at a high level, as with a wire touching battery voltage or a driver stage inside the module that will not switch off. TransEco's table for its AFCM v1.4 gives a short to power as the cause, with the MIL on and gas operation maintained. Ford names P2A29 in its Boss 302S code list. GM's bi-fuel Impala powers the cut-off solenoid on its tank only while the engine cranks or runs; a valve that remains live afterwards defeats the purpose of the lock, which is to hold gas in the cylinder when the vehicle stands or the fuel supply has been cut. Wiring mistakes after a conversion deserve a look. P2A28 is the low-side code for valve C.
P2A29 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyHard
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2A29
- Check engine light
- Cylinder C not sealed when the engine is off
Common causes of P2A29
- Most likelyValve C control wire in contact with battery voltage
- PossibleDriver stage for valve C will not switch off
- Less likelyValve C wired to a permanent feed after a conversion
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Alt fuel tank shutoff valve cWiring harnessAfcm
What each part of P2A29 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. |
| 29 | The exact fault in that area. |
What to do next
- Note P2A29 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 P2A29
What does P2A29 mean?
P2A29 means "Alternative Fuel Tank Shutoff Valve C Control Circuit High". P2A29 sets when the drive circuit of shutoff valve C sits at a high level, as with a wire touching battery voltage or a driver stage inside the module that will not switch off. It is a generic code, so it means the same on every make.
Is it safe to drive with P2A29?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2A29 fail an emissions test?
Yes, it can. P2A29 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 P2A29 to fix?
Difficulty: hard. A typical repair takes 0.5 to 3 hours of work. This is a job for a workshop.
Will P2A29 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.