P2A34 code meaning
AFCM Power Relay Control Circuit High
Powertrain system Generic code P2Axx codes Check engine light
What P2A34 means
With P2A34 the coil control line of the gas module power relay stays at high voltage even when the driver tries to pull it to ground. Either the wire has contact with a battery-fed circuit, or the coil draws so much current that the driver shuts itself off for protection. In both cases the relay does not close. The consequence is the opposite of P2A33: the alternative fuel module receives no switched supply, so gas operation is impossible, and a bi-fuel car falls back to gasoline from the start. Public documents for P2A34 are lacking; GM Europe treats the engine version P0687 on the 2010 Saab V6 with the same comparison of commanded against measured state. Ford's 2003 bi-fuel CNG design shows that the AFCM is a separate unit with its own power and relay outputs.
P2A34 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2A34
- Check engine light, depending on calibration
- Gas operation unavailable, bi-fuel vehicle runs on gasoline only
- Dedicated gas engine: cranks but does not start
Common causes of P2A34
- Most likelyControl wire shorted to a battery-fed circuit
- PossibleRelay coil with too low resistance overloading the driver
- Less likelyWrong relay type fitted after a repair
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Afcm power relayAfcmWiring harness
What each part of P2A34 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. |
| 34 | The exact fault in that area. |
What to do next
- Note P2A34 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 P2A34
What does P2A34 mean?
P2A34 means "AFCM Power Relay Control Circuit High". With P2A34 the coil control line of the gas module power relay stays at high voltage even when the driver tries to pull it to ground. It is a generic code, so it means the same on every make.
Is it safe to drive with P2A34?
Drive gently and only to a workshop. With P2A34 the car can go into limp mode (reduced power) to protect itself.
Will P2A34 fail an emissions test?
Yes, it can. P2A34 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 P2A34 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2A34 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.