Powertrain, generic (extended)

P27D6 Pressure Control Solenoid S Control Circuit Range/Performance

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P27D6 would indicate that the circuit of solenoid S is still closed but its electrical behaviour does not fit what the module commands. There is no public manufacturer description. On the Corvette dual-clutch transmission GM does compare target and estimated coil current of valve 5 (a 70 % gap held 60 ms, or a 400 mA gap held 300 ms, per 23OBDG07), yet files that result under the high-circuit code P27D8, so P27D6 stays unused there. CARB 13 CCR 1968.2 only sets the general duty to check actuator circuits. If another controller stores it, likely culprits are added resistance at a crimp, a coil whose ohms have drifted with age and heat, or a TCM output stage losing strength.

Likely causes

Added resistance at a crimp or pin
Solenoid S coil resistance out of specification
TCM output stage losing strength

Symptoms

  • MIL on
  • Uneven shifts into rod 5 gears

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€100–900
Time1–4 h

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

Parts involved

pressure control solenoid swiring harness

Related codes

P27D5P27D7P27D8P27D3P27CE

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