Powertrain, generic · Transmission

P08C6 Pressure Control Solenoid M Electrical

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

Collective code for an electrical fault of pressure control solenoid M without a finer split into open, low or high. No manufacturer documents it publicly. GM, the documented user of letter M on the Corvette dual clutch (synchronizer actuation valve 1), reports electrical faults only through the specific codes P08C8, P08CA and P08CB, which are derived from the diagnostic status of the low-side driver chip and confirmed after 150 ms. CARB requires a circuit check for every monitored transmission solenoid. A manufacturer setting P08C6 would point to coil, connector or harness of this valve; for the driver this means the warning light and restricted shifting on the affected shaft.

Likely causes

Solenoid coil open or shorted
Damaged connector or internal harness
Faulty driver stage in the transmission control module

Symptoms

  • Check engine light on
  • Restricted shifting or fallback mode

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–2,500
Time0.5–5 h

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

Parts involved

pressure control solenoid mtcmtransmission wiring

Related codes

P08C3P08C7P08C8P08CAP08CBP08BD

References: law.cornell.edu, gsi.ext.gm.com.