OBD-II code · Powertrain (generic, extended)
P28EB Shift Motor Position Not Learned
The TCM has not learned the end-stop calibration for the shift motor. Gear positions cannot be commanded with full precision until adaptation completes.
Is it safe to drive with P28EB?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyAdaptation lost after battery disconnect or TCM reset
- PossibleShift motor replaced without learn procedure
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
- 2–8 h
- Emissions test
- Usually unaffected
- Parts involved
- Shift Motor, Shift Motor Position Sensor, Tcm
Related codes
- P28E8Shift Motor Position Sensor Circuit High
- P28E9Shift Motor Position Sensor Circuit Low
- P28EAShift Motor Position Sensor Circuit Range/Performance
- P28ECShift Motor Position Sensor Exceeded Learning Limit
- P28EDElectric/Auxiliary Transmission Fluid Pump B Overspeed
- P28EEElectric/Auxiliary Transmission Fluid Pump B Underspeed
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.