P057B code meaning
Brake Pedal Position Sensor A Circuit Range/Performance
Powertrain system Generic code P05xx codes Check engine light
What P057B means
The brake pedal position sensor is an analogue 5 V sensor, usually Hall-type, giving the pedal position continuously instead of a switch – for brake lights, cruise control, stop-start, brake-throttle override and regenerative braking. GM (from about 2012) and Stellantis read it in the engine module, Saab's 9-4X and 9-5 in the body module; its learned rest position (about 1 V) must be relearned after replacement. P057B means the signal is valid but the pedal does not move as expected or the rest position is wrong. GM rates pedal movement once per ignition cycle while driving at 8 km/h or more without throttle (fail below 0.40, pass above 0.80), type A, one trip. If the module sees the pedal slightly pressed, it cuts power – GM and Stellantis bulletins name misinstalled or wrongly learned sensors.
P057B at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 1.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P057B
- Check engine light on
- Reduced power when accelerating
- Cruise control and stop-start inoperative
Common causes of P057B
- Most likelySensor misinstalled or not learned after replacement
- PossibleContact fault on 5 V reference or signal causes wrong rest position learning
- PossibleSensor faulty internally (sticking)
- Less likelyPedal mechanism stiff, floor mat
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Brake pedal position sensorSensor wiringEngine control module
What each part of P057B means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| 7B | The exact fault in that area. |
What to do next
- Note P057B 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 P057B
What does P057B mean?
P057B means "Brake Pedal Position Sensor A Circuit Range/Performance". The brake pedal position sensor is an analogue 5 V sensor, usually Hall-type, giving the pedal position continuously instead of a switch – for brake lights, cruise control, stop-start, brake-throttle override and regenerative braking. It is a generic code, so it means the same on every make.
Is it safe to drive with P057B?
Drive gently and only to a workshop. With P057B the car can go into limp mode (reduced power) to protect itself.
Will P057B fail an emissions test?
P057B is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P057B to fix?
Difficulty: medium. A typical repair takes 0.5 to 1.5 hours of work. This is a job for a workshop.
Will P057B clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.