P057C code meaning
Brake Pedal Position Sensor A Circuit Low
Powertrain system Generic code P05xx codes Check engine light
What P057C means
The brake pedal position sensor A is an analogue 5 V sensor giving pedal travel continuously; its rest position (about 1 V) is learned. GM reads it in the engine module from about 2012 and uses it as an enabling condition of transmission monitors – hence type A, warning lamp after one trip, unlike cruise control codes. On any circuit fault GM sets the pedal to 0 %, so brake detection relies on the brake light switch. P057C means the signal is too low – a short to ground: GM below 5 in 20 of 32 samples. GM bulletins for 2012–14 pick-ups and SUVs name connector X205 under the left defroster duct, with cruise, brake light and stability messages and reduced power.
P057C at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 2 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P057C
- Check engine light on (GM, one trip)
- Cruise control, brake light or stability functions restricted
- Reduced power when accelerating
Common causes of P057C
- Most likelyConnector or terminals at sensor or inline connector (GM X205) loose, pushed back or corroded
- PossibleSignal or 5 V reference shorted to ground
- PossibleSensor faulty internally
- Less likely5 V reference pulled down by another sensor
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 P057C 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. |
| 7C | The exact fault in that area. |
What to do next
- Note P057C 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 P057C
What does P057C mean?
P057C means "Brake Pedal Position Sensor A Circuit Low". The brake pedal position sensor A is an analogue 5 V sensor giving pedal travel continuously; its rest position (about 1 V) is learned. It is a generic code, so it means the same on every make.
Is it safe to drive with P057C?
Drive gently and only to a workshop. With P057C the car can go into limp mode (reduced power) to protect itself.
Will P057C fail an emissions test?
Yes, it can. P057C 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 P057C to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P057C clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.