OBD-II trouble code
P0751: Shift Solenoid "A" Performance or Stuck Off
SAE J2012: shift solenoid A performance or stuck off. The letter is this controller's label. On a GM 4L60-E, A happens to be the 1–2 solenoid. On other units it is a different clutch, and ATRA bulletin 794 shows Ford SSA on a 4F27E is Mazda SSD. Look up the chart before ordering a 1–2 solenoid.
Quick facts
- System
- Powertrain
- Category
- Transmission / Shift Control
- Severity
- High severity
- Drivable
- Usually safe to drive short-term
- Repair cost range
- $300 – $900 (simple shift solenoid replacement)
- DIY difficulty
- Advanced DIY
One of 42 shift solenoid codes
P0751 sits in a grid: one axis is which solenoid the letter refers to, the other is what went wrong with it. Each cell is a genuinely different fault with its own diagnosis — but codes from the same row or column often appear together, and what a pairing means is usually the fastest way in. The hub page lays out all 42 and explains how to read them against each other.
See all shift solenoid codes →Browse every code in P0700–P0799, or start from the full code library.
What does P0751 mean?
Performance or stuck off means the controller commanded a result from solenoid A and the measured result did not follow. On a hydraulic monitor the measurement is gear ratio from input speed and output speed. A 6T40 sets P0751 when 1st is commanded and the ratio and slip are wrong for that calibration. A 2001 Grand Prix chart sets P0751 only when commanded gear and measured ratio disagree, and that test does not run if the electrical code P0753 is already stored. If P0753 is present, fix the circuit. The performance test is not even enabled.
Normally open and normally closed solenoids make 'off' mean opposite hydraulic things. 4L60-E shift solenoids are normally open exhaust valves. A 6T40 shift solenoid blocks flow when commanded off and builds signal pressure when commanded on. The application chart for this transmission is what 'stuck off' means here. ATRA's 2006 charts show SSA on in 1st on some units and off in 1st on others. There is no universal gear and no ohm band that covers both an on/off solenoid and a linear solenoid in the same valve body.
Common causes
- An external connector with fluid, corrosion, or a terminal that is not latched
- Low fluid, or fluid that has not been checked at the temperature and engine speed this procedure specifies
- Input or output speed that is wrong, so the ratio the monitor uses is wrong
- Solenoid A mechanically stuck off or not stroking, after the circuit test for P0753 is clear
- A valve-body bore that will not let a new solenoid seal, found when the pan is down and the bore is inspected
- A wiring fault between the module and the case connector
Symptoms
- Check engine light with P0751
- The shift this chart assigns to solenoid A is late, missing, or flares
- A failsafe gear, which is the gear this calibration holds, not a fixed second or third
- Engine speed high for the road speed while that failsafe gear is held
- P0753 stored with it, which on the Grand Prix chart disables this performance test
- A speed-sensor code stored ahead of the ratio code
Diagnostic steps
- 1.Record commanded gear, solenoid A command, input speed, output speed, and every companion code. If P0753 or a speed-sensor code is stored, that circuit comes first. The 2001 Grand Prix chart does not run the P0751 test while P0753 is set.
- 2.Look up solenoid A on this application chart. Write down the clutch and the gears. Do not order a 1–2 solenoid from the letter. ATRA 794 is the counterexample: Ford SSA on the 4F27E is Mazda SSD.
- 3.Check fluid the way this transmission specifies. A 6L80 level check in the ATRA introduction handout is at idle, 86–122°F, at a pan plug. A 6T40 drain-and-fill note checks at idle, 185–203°F, engine running, and warns that the fluid is hot. Engine-off and engine-running procedures both exist. Use the one printed for this unit.
- 4.Ignition off. Inspect the case connector, then measure solenoid A against this transmission's specification with the solenoid disconnected from the module. A 4L60-E shift solenoid and the EPC in the same connector use different ohm bands. There is no 10–30 ohm substitute.
- 5.If the ratio error matches solenoid A's clutch and the coil is in range, the next branch is the valve, the bore, or the clutch that chart names. Drop the pan only then, on a lift or stands, with the fluid cool enough not to scald.
- 6.Verify on a recorded drive, passenger reading the tool: commanded gear against the ratio, in the gear this chart assigns to solenoid A.
Repair cost
$300 – $900 (simple shift solenoid replacement)
AutoZone's article 'Bad Torque Converter vs Bad Transmission' prices a simple solenoid replacement at $300–$900 parts and labor. That is the pair. A rebuild in the same article is $1,800–$3,500 and a replacement is $4,000–$8,000. RepairPal has no shift-solenoid estimator. Its brake-shift-interlock estimator is a console part and is the wrong job. RepairPal's transmission fluid change, updated 3 September 2026, averages $294–$356. Dropping the pan includes fluid. That average is not the solenoid total, and a drain-and-fill is not a chemical flush.
Estimate your repair
Run the numbers for your vehicle
Open the Repair Cost Estimator with transmission shift solenoid replacement preselected. Adjust labor rate and vehicle category to fit your situation.
DIY vs shop
This is an advanced DIY job. It typically requires specialty tools, scan-tool access, lifting equipment, or careful sequencing to avoid causing new failures. Plan for extended downtime and have a backup vehicle. Most owners are better served by a shop that has done this repair before.