P27C4Pressure Control Solenoid P Intermittent
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P27C4 indicates that solenoid P works most of the time but its circuit or response briefly drops out. No manufacturer documents the code publicly; GM's Corvette DCT table 23OBDG07 and Ford's TR9070 list, which both use this solenoid as synchronizer valve 3, only publish hard faults such as P27C5, P27C7, P27C8 and the hydraulic codes P27C1/P27C2. CARB 13 CCR 1968.2 counts transmission solenoids among monitored outputs. Intermittent dropouts usually come from fretting corrosion at terminals, a conductor broken inside its insulation, or a solenoid whose winding opens when it reaches operating temperature. Logging data while flexing the harness and warming the unit helps catch it.
- What you may notice
- MIL that comes and goes
- Occasional harsh or missed shift
- Likely causes
- LikelyFretting corrosion on connector terminals
- PossibleWire strand broken inside intact-looking insulation
- RareSolenoid winding that opens at operating temperature
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.