P2A43 code meaning
Alternative Fuel Tank B Pressure Sensor Circuit Low
Powertrain system Generic code P2Axx codes Check engine light
What P2A43 means
P2A43 is stored when the signal of the tank B pressure sensor drops below its lower electrical limit, a level that no real tank pressure produces. The usual reasons are a signal wire grounded against the frame, a missing 5 V reference or an internal short in the sensor. For the tank A sensor, TransEco's AFCM list puts exactly these faults under its Low code, with a substitute value of 3600 psi and the lamp switched on in both dedicated and bi-fuel setups. Because a low signal looks like an empty cylinder, the gauge may drop to zero and tank B may be locked out although it still holds gas. No manufacturer documents P2A43 itself. Ford's 2014 Boss 302S table carries the tank A version P01A0 as a lamp code, a sign that the family is treated as emission-relevant.
P2A43 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyHard
- Typical labor1 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2A43
- Check engine light
- Gauge drops to empty for tank B
- Less usable gas range
Common causes of P2A43
- Most likelySignal wire shorted to ground
- Possible5 V reference open or pulled down by another sensor
- PossibleInternal short in the tank B sensor
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Alt fuel tank b pressure sensorWiring harnessAfcm
What each part of P2A43 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. |
| 43 | The exact fault in that area. |
What to do next
- Note P2A43 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 P2A43
What does P2A43 mean?
P2A43 means "Alternative Fuel Tank B Pressure Sensor Circuit Low". P2A43 is stored when the signal of the tank B pressure sensor drops below its lower electrical limit, a level that no real tank pressure produces. It is a generic code, so it means the same on every make.
Is it safe to drive with P2A43?
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 P2A43 fail an emissions test?
Yes, it can. P2A43 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 P2A43 to fix?
Difficulty: hard. A typical repair takes 1 to 3 hours of work. This is a job for a workshop.
Will P2A43 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.