P27EETransmission Range Control A Position Sensor/Switch Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- The opposite of P27ED: the position sensor of mode valve A reads higher than any valid state. GM's TCM tables for the T87A nine-speed of 2018 and the rear-drive ten-speed of 2020 set P27EE when the raw signal exceeds 2.538 V for 0.100 s inside a 0.163 s sample, describing it as a short to voltage on the sensor circuit; the MIL comes on at once (Type A). A sensor that has lost its ground return can also float upward and mimic a short. While the fault is present, GM blocks the plausibility test P27EC and several pressure checks, since the valve position is unknown. Repairs usually involve the internal harness or the sensor; valve B reports the same condition as P27F2, the open band as P27EB.
- What you may notice
- MIL on from the first trip
- Range changes restricted, possible reduced mode
- Likely causes
- LikelySensor signal shorted to a voltage source
- PossibleSensor ground open, signal drifts high
- RareHall sensor output stage faulty
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €150 – €2,000
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.