Powertrain, generic · Transmission

P08CB Pressure Control Solenoid M Control Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

GM uses this code on the Corvette's Tremec dual clutch for synchronizer actuation valve 1 (odd-gear shaft) in two situations. First, a short to battery voltage: with the low-side driver on, a sense voltage above 0.7, 0.9 or 1.1 V (±0.1 V), depending on supply voltage, counts as a shorted load, confirmed after 150 ms. Second, a short to a neighbouring output: at shutdown every output is switched on in turn, a cross-reaction is stored in memory and the code is set at the next start. Type A, MIL at once. The check pauses while P0882 or P0883 is present. A valve shorted to power cannot be switched off, so the transmission will usually go into a fallback mode.

Likely causes

Control wire shorted to battery voltage
Short to an adjacent solenoid wire in the internal harness
Defective driver stage in the transmission control module

Symptoms

  • Check engine light on immediately
  • Fallback mode with restricted gears
  • Code may appear right after starting

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 mwiring harness

Related codes

P08C3P08C8P08C9P08CAP08C2P27C0

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