P08C9 code meaning
Pressure Control Solenoid M Control Circuit Range/Performance
Powertrain system Generic code P08xx codes Check engine light
What P08C9 means
Meant for a control circuit of pressure control solenoid M that is not open or shorted but behaves implausibly, for instance a coil current that does not follow the command. No manufacturer documents this code publicly. GM, which uses letter M for synchronizer actuation valve 1 of the Corvette dual clutch, publishes only open, low, high and the two hydraulic codes for it; its tables do describe a current check that compares target and estimated current (more than 70 % for 60 ms or more than 400 mA for 300 ms), but without naming P08C9. CARB requires monitoring of transmission solenoids. Possible causes are a coil with drifting resistance, contact resistance or supply voltage problems; shift quality may suffer.
P08C9 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor0.5 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P08C9
- Check engine light on
- Uneven shift quality
Common causes of P08C9
- Most likelyCoil resistance out of specification
- PossibleHigh contact resistance at connector pins
- Less likelyUnstable supply voltage to the transmission module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Pressure control solenoid mWiring harness
What each part of P08C9 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 8 | Area: transmission. |
| C9 | The exact fault in that area. |
What to do next
- Note P08C9 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P08C9
What does P08C9 mean?
P08C9 means "Pressure Control Solenoid M Control Circuit Range/Performance". Meant for a control circuit of pressure control solenoid M that is not open or shorted but behaves implausibly, for instance a coil current that does not follow the command. It is a generic code, so it means the same on every make.
Is it safe to drive with P08C9?
Drive gently and only to a workshop. With P08C9 the car can go into limp mode (reduced power) to protect itself.
Will P08C9 fail an emissions test?
Yes, it can. P08C9 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P08C9 to fix?
Difficulty: hard. A typical repair takes 0.5 to 5 hours of work. This is a job for a workshop.
Will P08C9 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.