Powertrain, generic · Transmission

P086D Neutral Position Sensor A Circuit High

Check engine lightUsually off
EmissionsNot relevant
Drive cycleNot required
Limp modeNo

Neutral position sensor A is a three-wire Hall sensor on the shift shaft of a manual gearbox that reports neutral to the engine module; start-stop may only switch the engine off in neutral. Audi uses it as sender G701 on the Q3 and A3, GM on the 2019 Corvette ZR1 manual, where its faults suspend the gear ratio checks. Thresholds and MIL status are not published. P086D means the signal is above its upper limit: an open signal or ground wire or a short to voltage. Audi's bulletin for the 2019–20 Q3 and 2022–23 A3 found the wires to G701 laid too short, so shifting pulled them apart; all three are lengthened by 20 mm. The cluster shows a start system fault.

Likely causes

Wire to the neutral sender broken or laid too short (Audi G701)
Connector loose or corroded
Sensor open internally
Ground wire open

Symptoms

  • Start system fault message (Audi)
  • Start-stop not working
  • Fault appears after gear changes

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–300
Time0.5–1.5 h

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

Parts involved

neutral position sensorsensor wiringengine control modulemanual transmission

Related codes

P086AP086BP086CP086EP086FP08B0

References: static.nhtsa.gov, gsi.ext.gm.com, patents.google.com.