Powertrain, generic (extended)

P2857 Clutch A Pressure Engagement Performance/Too Low

Check engine lightOn

EmissionsRelevant

Drive cycleNot required

Limp modePossible

P2857 reports that clutch A did not build up enough holding force when the control unit asked it to engage, so the expected ratio or torque transfer never appeared. Mitsubishi documents it for the CVT with two-speed auxiliary gearbox fitted to Mirage and Mirage G4 models from 2014 to 2022: while that gearbox is shifted into its first ratio, a measured ratio of 2.232 or more for 2 s counts as a fault, provided the pedal is at least 7.8 % open, the engine turns 450 rpm or more and D or B is selected. Nissan lists the same number as a clutch A pressure fault on the Kicks and Versa CVT, and Mercedes-Benz uses it on the 8G-DCT when multidisk clutch 1 fails to close. Drivers typically notice slipping, a flaring engine on take-off or a reduced-power mode.

Likely causes

Control valve (valve body) not delivering the commanded apply pressure to clutch A

Worn clutch A linings or leaking piston seals

Low, aerated or aged transmission fluid

Symptoms

Engine speed flares on take-off without matching acceleration
Hesitation or reduced power, transmission emergency mode
Warning lamp with stored transmission code

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 aclutch actuator atransmission pump

Related codes

P2858 P2859 P2853 P2855 P286B P2871

References: static.nhtsa.gov, static.nhtsa.gov, static.nhtsa.gov, performanceparts.ford.com.