OBD-II code · Powertrain (generic, extended)
P284B Shift Fork C Stuck
Shift fork C cannot leave its current engagement position when the actuator commands movement. Mechanical jam or actuator without travel.
Is it safe to drive with P284B?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyShift fork mechanically jammed
- PossibleSynchroniser teeth damaged
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
- 4–14 h
- Emissions test
- Usually unaffected
- Parts involved
- Shift Fork C, Shift Fork Actuator C, Synchroniser Assembly
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.