Faulty brake pedal position sensor, or an internal fault giving a high signal; Pedal sensor out of adjustment, loose, or knocked out of position after pedal or bracket work; Corroded, damaged or loose connector terminals at the sensor; Signal wire shorted to a voltage supply, or chafed wiring in the loom; Open circuit in the sensor ground wire, which pulls the signal high; Damaged pedal bracket or worn pedal mechanism causing a bad reading; Fault inside the control unit's sensor input or reference supply.

P057D

Brake Pedal Position Sensor A Circuit High.

Generic
Powertrain
Generic code
Medium severity

How this code is built

P: SystemPowertrain
0: Defined bySAE, the same on every car
5: AreaVehicle speed, idle control and auxiliary inputs
7D: FaultThe specific fault in that area

What it means

P057D means the engine or powertrain control module saw the signal from the brake pedal position sensor (circuit A) sit higher than its expected voltage range. This usually points to a short to voltage, an open ground, or a faulty sensor. The control unit uses this signal to know when the brakes are applied, so it affects things like cruise control, brake light logic and torque management. The exact sensor design and signal range vary by model, so check the manufacturer data for the vehicle.

Symptoms

Engine warning light on
Cruise control or speed limiter not working
Brake lights stuck on, or not working at all
Reduced power or limited throttle response on some models
Stop-start system disabled
Gearbox shift lock or key release problems on some models

Possible causes

Faulty brake pedal position sensor, or an internal fault giving a high signallikely
Pedal sensor out of adjustment, loose, or knocked out of position after pedal or bracket worklikely
Corroded, damaged or loose connector terminals at the sensorlikely
Signal wire shorted to a voltage supply, or chafed wiring in the loompossible
Open circuit in the sensor ground wire, which pulls the signal highpossible
Damaged pedal bracket or worn pedal mechanism causing a bad readingrare
Fault inside the control unit's sensor input or reference supplyrare

How to diagnose

Read all stored and pending codes and record the freeze frame data, noting any related brake switch, cruise control or reference voltage codes
Check the brake lights work correctly and that they go off when the pedal is released
Inspect the sensor, connector and wiring for damage, corrosion, water ingress, chafing or signs of earlier repairs
Look at the live data for the brake pedal sensor and compare the reading with the pedal released and fully pressed; it should change smoothly and stay within the specified range
Check the sensor mounting and pedal position against the manufacturer's specification, and check the pedal and bracket for damage or movement
With the connector unplugged and the ignition on, check the reference supply and ground against the wiring diagram for the model
Check the signal wire for a short to voltage and for continuity back to the control unit
If the wiring and supply are good, test or substitute the sensor following the manufacturer's procedure before suspecting the control unit

How to fix

Replace the brake pedal position sensor if it is faulty, then adjust or calibrate it if the manufacturer requires it
Reposition, secure or readjust the sensor to the specified setting
Clean or repair the connector terminals, or replace the connector
Repair or replace damaged wiring, including any short to voltage or open ground
Repair or replace a damaged pedal bracket or pedal assembly
Repair or replace the control unit only once all other causes are ruled out and the manufacturer's tests confirm it

Can I keep driving?

Medium severity

The car can usually be driven for a short time, but get it checked soon because the brake light signal and some driver aids may not work properly. If the brake lights are not working or are stuck on, or the car loses power, limit driving until it is fixed.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.