Powertrain, generic · Transmission

P08AB Clutch Pedal Position Sensor A Circuit Intermittent/Erratic

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modeNo

P08AB is meant for a clutch pedal sensor A signal that jumps, drops out briefly or changes faster than a foot could move the pedal, without staying out of range long enough for the low or high codes. No manufacturer documents this code publicly. GM's published tables for the same sensor use only P08A8, P08A9, P08AA and P08AC, and its low/high checks need 400 of 500 bad samples, so short dropouts would go unnoticed there; Ford names only low, high and A/B correlation. CARB requires such inputs to be checked for circuit faults and plausibility. In practice the cause is usually a loose connector or a wire that breaks inside its insulation as the pedal moves. Start-stop and cruise control may cut out intermittently.

Likely causes

Loose or worn terminals in the pedal sensor connector
Wire breaking inside its insulation where the harness flexes with the pedal
Worn sensor track causing signal dropouts at certain pedal positions
Moisture or corrosion in the footwell connector

Symptoms

  • Start-stop or cruise control cutting out intermittently
  • Warning lamp that comes and goes
  • Erratic clutch pedal value in scan tool data while the pedal is held still

Repair estimate

DifficultyMediumDIY possible
Parts and labour€50–300
Time0.5–2 h

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

Parts involved

clutch pedal position sensor awiring harnessecm

Related codes

P08A7P08A8P08A9P08AAP08B8

References: law.cornell.edu, gsi.ext.gm.com.