P2738Pressure Control Solenoid F Control Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2738 reports a control line on solenoid F that reads too low, which in practice means a short to ground. In GM's 2025 table 25OBDG03A an impedance below 0.5 Ohm between the signal and controller ground, lasting 0.3 s inside a 0.5 s sampling period, is a Type A fault in one trip; the valve there controls a clutch on the nine- or ten-speed, line pressure on the eight-speed or the CVT binary pump. The eight-speed table of 2016 uses the same timing. The Corvette dual-clutch TCM tests the clutch cooling valve with its driver switched on and sets P2738 when the measured pin voltage remains below roughly 1.7 V for 150 ms. Ford's TR9070 labels the same condition shorted switch on the odd clutch cooling valve. A grounded line can energise the valve permanently.
- What you may notice
- MIL on and fail-safe gear
- Harsh engagements or clutch drag
- Likely causes
- LikelyControl wire chafed through to ground
- PossibleShorted turns in solenoid F
- PossibleFluid or metal debris bridging connector pins
- RareFaulty TCM output stage
- 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 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.