P285A
Clutch B Pressure Disengagement Performance/Too Low
Dual-clutch transmission
Generic OBD-II
Medium
What it means
P285A means clutch B in a dual-clutch transmission isn't disengaging properly because its apply/release pressure is too low or out of spec. Expect shudder, slipping, hesitation, or even stalling, and possibly limp mode. It does not cause an engine no-start, but the transmission needs attention.
Medium
Can I keep driving? Reduced — clutch B may slip or drag, causing shudder, hesitation, or stalling; the transmission may enter limp mode.
Common symptoms
What you'll notice
- Check-engine light on
- Clutch shudder, slipping, or hesitation on takeoff and shifts
- Stalling or lurching when stopping or shifting
- Transmission in limp/failsafe mode
Common causes
Most likely first
- Low or contaminated transmission/clutch fluidLikely
- Worn clutch B or a failing clutch actuatorCommon
- Faulty pressure control solenoid or mechatronic unit for clutch BCommon
- Damaged or corroded actuator wiring/connectorLess often
- Clutch adaptation out of rangeLess often
How to diagnose & fix
Work through it in order
- Scan freeze-frame and related clutch codes (P2859, P0741).
- Check transmission fluid level and condition; use the correct dual-clutch fluid spec.
- Inspect the clutch actuator/solenoid wiring and connector.
- Test clutch B apply/release pressure against spec and run clutch adaptation.
- Repair or replace the mechatronic/clutch components as indicated; clear and road-test.
FAQ
Quick answers
Is it safe to drive with P285A?+
Short-term gentle driving may be possible, but a clutch that won't disengage cleanly can shudder or stall and will wear faster. Have it checked soon.
Can I just clear P285A?+
The code returns once clutch B pressure is out of spec again; the fluid, actuator, or clutch itself must be addressed.
Related codes
Often seen with P285A
Read & clear P285A yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX