OBD-II code · Powertrain (generic, extended)

P27ED Transmission Range Control A Position Sensor/Switch Circuit Low

The position sensor or switch of transmission range control channel A reports a circuit low condition. The TCM cannot verify the actuator position reliably.

Is it safe to drive with P27ED?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelySignal wire shorted to ground
  • PossibleInternal short in position sensor
  • Less likelyConnector pins corroded - high contact resistance

Symptoms

  • Check engine or transmission warning light on
  • Harsh, delayed, or missing shifts
  • Possible limp mode (locked in one gear)
  • Slipping or shuddering during gear changes

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
1–4 h
Emissions test
Usually unaffected
Parts involved
Range Control Position Sensor A, Wiring Harness, Tcm

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.