Transmission · Powertrain · generic (SAE-defined)
P0751: Shift Solenoid "A" Performance/Stuck Off
P0751 means the transmission computer commanded shift solenoid A on, but gear ratio or pressure feedback shows the solenoid behaved as if it stayed off or performed poorly.
Standard title per SAE J2012 / ISO 15031-6 · Updated 2026-11-07 · By CarWhere Research
How P0751 sets
The powertrain or transmission control module (PCM/TCM) calculates the actual gear ratio from input and output speed sensors and compares it to the gear it commanded. When the result matches what would happen if shift solenoid A failed to apply, the module sets P0751. The electrical circuit may test fine because this is a mechanical or hydraulic performance fault. Gear assignments for solenoid A vary by manufacturer.
Common causes of P0751
Roughly most likely first; the actual cause depends on the vehicle and needs testing to confirm.
- Low or dirty transmission fluid
- Shift solenoid A sticking or clogged with debris
- Worn or sticking shift valve in the valve body
- Internal fluid leaks from worn seals or valve bores
- Worn clutch pack for the affected gear
- Faulty speed sensor giving incorrect ratio data
P0751 symptoms
- Check engine light on
- Starts in a higher gear than normal
- Missing one or more upshifts
- Delayed or slipping shifts
- Limp mode in some vehicles
How P0751 is diagnosed
- Check fluid level and condition; look for debris or a burnt smell.
- Scan for related ratio, speed sensor, and pressure codes.
- Identify which gears solenoid A affects on this transmission.
- Road test while monitoring commanded gear versus actual ratio in live data.
- Verify the solenoid electrically, then test its hydraulic operation or apply with air if accessible.
- Inspect the valve body and pan contents for debris or wear.
Typical fixes for P0751
- Service the fluid and filter
- Replace shift solenoid A
- Clean or repair the valve body
- Repair internal leaks or worn clutches during overhaul
- Replace a faulty speed sensor if it caused false ratio data
Replace parts only after testing confirms the cause — a code names the circuit or condition that failed a check, not necessarily the faulty part. We don’t publish per-repair prices; for what households actually spend on upkeep, see car repair costs.
Manufacturer notes
Commonly reported on GM 4L60-E family transmissions, where solenoid A is often the 1-2 shift solenoid. Assignments differ on other transmissions; check factory service information.
Related codes & warning lights
P0751 FAQ
What does code P0751 mean?
P0751 means the transmission computer commanded shift solenoid A on, but gear ratio or pressure feedback shows the solenoid behaved as if it stayed off or performed poorly. The standard definition is "Shift Solenoid "A" Performance/Stuck Off."
Can I drive with a P0751 code?
Drive only as needed to reach a repair shop. With a solenoid stuck off, the transmission may start in the wrong gear or skip shifts, and slipping can cause internal wear.
Why does P0751 appear when the wiring tests good?
This code describes a performance fault, not a circuit fault. The solenoid can have normal resistance but still stick mechanically or be unable to move fluid because of debris or valve wear.
Can a clogged filter cause P0751?
A restricted filter or heavily contaminated fluid can starve the hydraulic circuit and make a solenoid appear stuck, so fluid condition is one of the first checks.
Keep researching
More transmission codes
Sources
- SAE J2012 — Diagnostic Trouble Code Definitions (standard code titles)
- ISO 15031-6 — Road vehicles: communication between vehicle and external equipment for emissions-related diagnostics, Part 6: Diagnostic trouble code definitions
- U.S. EPA — Vehicle Emissions Inspection and Maintenance (I/M) programs
- U.S. EPA, 40 CFR 86.1806-17 — Federal onboard diagnostics requirements for light-duty vehicles
General information written by CarWhere Research, not a diagnosis of your vehicle. Manufacturers can add their own sub-definitions and test conditions; confirm with the factory service information for your year, make and model. Before paying for a repair, check NHTSA for open recalls and your warranty booklet: federal law requires an emissions warranty on major emission-control parts such as the catalytic converter and engine computer.