Powertrain, generic · Vehicle speed, idle control and auxiliary inputs

P057E Brake Pedal Position Sensor A Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

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. P057E means implausibly fast signal jumps within the valid range: GM sets it at jumps above 11 in 5 of 20 samples. Brief interruptions can also make GM's engine module learn a wrong rest position – it then sees the brake pressed and cuts power; GM names fretting at the 5 V reference or signal.

Likely causes

Loose contact or fretting corrosion at sensor or inline connector
Broken or chafed wire near the pedal
Sensor worn internally (signal jumping)
Interference on the 5 V reference

Symptoms

  • Check engine light on (GM)
  • Sporadic power reduction when accelerating
  • Cruise control cutting out sporadically

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–300
Time0.5–2.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

brake pedal position sensorsensor wiringengine control module

Related codes

P057AP057BP057CP057DP0571

References: gsi.ext.gm.com, gsi.ext.gm.com, static.nhtsa.gov, gm-techlink.com.