OBD-II code · Powertrain (generic)

P0909 Gate Select Control Error

The TCM detects that the gate select actuator does not reach the commanded position within tolerance. Mechanical bind, weak actuator, or sensor offset.

Is it safe to drive with P0909?

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

Common causes

  • Most likelySelector mechanism binding
  • PossibleActuator force degraded

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
Hard
DIY friendly
Best left to a mechanic
Typical labour
2–7 h
Emissions test
Usually unaffected
Parts involved
Gate Select Actuator, Gate Select Position Sensor, Tcm

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