P0751Shift Solenoid A Performance/Stuck Off
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- A shift solenoid is an electrically switched valve in the valve body; together the solenoid states select the gear, and the module checks the result by gear ratio, slip or a pressure switch – the pattern of wrong gears shows which solenoid hangs off or on. P0751 means solenoid A is commanded on but valve, clutch or gear do not follow. GM's 6T70 flags a ratio of 1.34–1.48 with slip of 400 rpm for 0.3 s eight times and locks out first gear; GM 4-speeds recognise the pattern 2-2-3-3; both after two trips. Allison checks its pressure switch for 5 s after one trip. Ford's 'functionally failed off' covers the whole clutch circuit, and its 10R80 and 8F35 bulletins show purely mechanical causes such as a leaking clutch cylinder.
- What you may notice
- Gears missing or skipped
- Pulling away in the wrong gear, weak acceleration
- Limp mode or gear lock-out
- Check engine light
- Likely causes
- LikelyShift spool in the valve body sticking (dirt, debris)
- PossibleInternal leak or clutch fault in the circuit
- PossibleSolenoid mechanically sluggish or screen clogged
- PossibleFluid level or quality wrong
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €200 – €3,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.