P2A0C code meaning
Manifold Absolute Pressure Sensor B Circuit Low
Powertrain system Generic code P2Axx codes Check engine light
What P2A0C means
P2A0C reports that the MAP B signal voltage is too low. Manifold pressure sensors are usually three-wire parts fed from a 5 V reference; a signal close to zero means a broken reference or signal wire, a ground short or a dead sensor, because even deep vacuum would not pull a healthy sensor down that far. GM documents the code for the Corvette's LT6 V8, whose sensor B measures the manifold pressure of bank 2: a reading below 0.5 V for 1.5 s sets it after one trip. The bank-1 sensor reports the same condition as P0107. Once the signal is lost the module falls back on a modelled pressure for that bank, so the engine keeps running, but response and smoothness may suffer and power may be cut back.
P2A0C at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyEasy, DIY possible
- Typical labor0.3 to 1.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2A0C
- Check engine light on
- Sluggish response or rough running
- Possible reduced engine power
Common causes of P2A0C
- Most likely5 V reference or signal wire open
- PossibleSignal wire shorted to ground
- PossibleSensor B failed internally
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
MAP sensor bWiring harnessECM
What each part of P2A0C 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. |
| 0C | The exact fault in that area. |
What to do next
- Note P2A0C 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 P2A0C
What does P2A0C mean?
P2A0C means "Manifold Absolute Pressure Sensor B Circuit Low". P2A0C reports that the MAP B signal voltage is too low. It is a generic code, so it means the same on every make.
Is it safe to drive with P2A0C?
Drive gently and only to a workshop. With P2A0C the car can go into limp mode (reduced power) to protect itself.
Will P2A0C fail an emissions test?
Yes, it can. P2A0C 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 P2A0C to fix?
Difficulty: easy. A typical repair takes 0.3 to 1.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P2A0C clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.