Powertrain, generic (extended)

P285A Clutch B Pressure Disengagement Performance/Too Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

With P285A the module reports a release-side pressure fault involving clutch B. Mitsubishi's Mirage CVT evaluates it while the auxiliary gearbox is commanded into its second stage: a ratio that remains within 10 % of the first stage (1.639–2.003) for 0.5 s, or that drops to 0.500 or below or climbs to 1.500 or above for 0.2 s, sets the code. On the Nissan Kicks and Versa the number carries extra weight: if it appears together with P0875, the fluid pressure switch D code, Nissan has the control valve replaced straight away without the belt inspection required for the other codes. In daily driving the car may refuse the upper stage, flare between shifts or drop into a limp program, while the lower stage often stays usable.

Likely causes

Defective control valve, especially when P0875 is stored at the same time
Leak in the clutch B circuit preventing a clean handover
Faulty clutch pressure switch or its wiring

Symptoms

  • Upper stage or even gears not available
  • Flare between shifts, then a hard engagement
  • Limp mode with warning lamp

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€150–4,500
Time1–10 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

clutch bclutch actuator btransmission pump

Related codes

P2859P2858P2874P2877P0875

References: static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov.