Powertrain, generic · Transmission

P086E Neutral Position Sensor A Circuit Intermittent/Erratic

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. P086E means the signal jumps out of range for short moments or changes implausibly fast, typically a loose contact or a chafed wire that moves with the shift shaft. Audi often stores it together with P086D when the too-short G701 wiring only breaks contact now and then.

Likely causes

Wire at the neutral sender strained or cracked (Audi G701)
Loose contact or corrosion in the connector
Sensor or magnet target loose

Symptoms

  • Start-stop works only at times
  • Start system warning comes and goes

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

P086AP086BP086CP086DP08B1

References: static.nhtsa.gov, patents.google.com, law.cornell.edu.