OBD-II code · Powertrain (generic, extended)
P285A Clutch B Pressure Disengagement Performance/Too Low
Clutch B disengagement pressure is below the calibrated minimum. Clutch may not separate cleanly under load.
Is it safe to drive with P285A?
The car may go into limp mode (reduced power). Get it diagnosed before a long trip.
Common causes
- Most likelyHydraulic pump output pressure low
- PossiblePressure regulator characteristic drift
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
- 3–12 h
- Emissions test
- Usually unaffected
- Parts involved
- Clutch B, Clutch Actuator B, Transmission Pump
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.