Home›Trouble Codes›P0747

P0747 — Pressure Control Solenoid Stuck

Generic OBD-II · all makesPowertrain (engine & transmission)

P0747 is a transmission‑related OBD‑II fault code indicating that the pressure control solenoid is stuck in one position and is not cycling as commanded by the powertrain control module (PCM/TCM). When the solenoid fails to regulate line pressure properly, the transmission may shift harshly, slip, or enter a fail‑safe (limp) mode. The code is set when the PCM detects that the solenoid’s state does not match the expected on/off or PWM command.

Symptoms

What causes it — most likely first

1. Faulty pressure control solenoid

The solenoid itself can mechanically jam open or closed, preventing proper line‑pressure regulation.

2. Dirty or contaminated transmission fluid

Fluid that is dark, burnt, or contains debris can clog or bind the solenoid, causing it to stay in one position.

3. Wiring or connector problem

A damaged harness, corroded terminals, or an intermittent open/short can keep the PCM from correctly commanding the solenoid.

4. Low or degraded fluid level

Insufficient fluid reduces line pressure and can make the solenoid appear stuck as the system cannot maintain proper pressure.

5. Faulty valve body

The valve body houses the solenoid; wear or scoring can prevent the solenoid’s plunger from moving freely.

6. Rare PCM/TCM fault

In very few cases, a software issue or electrical fault within the control module may send incorrect commands, but this is far less common than the other causes.

How it's diagnosed

  1. Connect an OBD‑II scan tool to confirm P0747 and note any additional transmission fault codes.
  2. Inspect the transmission fluid level and condition; top up or replace fluid if it is low, dark, or burnt.
  3. Visually examine the wiring harness and connector at the pressure control solenoid for damage, corrosion, or looseness.
  4. Measure the solenoid’s resistance with a multimeter and compare it to the manufacturer’s specification.
  5. If the scan tool supports actuation, command the solenoid on/off to verify proper movement and listen for operation.
  6. If the solenoid, wiring, and fluid are all within spec, inspect the valve body for wear or blockage and replace if necessary.
  7. Only after all other possibilities are ruled out, consider PCM/TCM replacement or reprogramming as a last resort.

Code facts & related codes

SystemPowertrain (engine & transmission)
StandardizationSAE generic — identical on every make
Related codesP0740 — Torque Converter Clutch CircuitopenP0741 — Torque Converter Clutch Circuit PerforP0742 — Torque Converter Clutch Circuit StuckP0743 — Torque Converter Clutch Circuit ElectrP0744 — Torque Converter Clutch Circuit IntermP0745 — Pressure Control Solenoid

Frequently asked

Can a bad PCM cause P0747?

While the PCM controls the solenoid, failures of the module itself are rare for this code. Most instances are traced to the solenoid, fluid, or wiring.

Will cleaning the transmission fluid fix the code?

If the fluid is contaminated, a fluid change may restore proper solenoid operation, but if the solenoid is physically failed, replacement will be necessary.

Do I need to replace the whole transmission if the solenoid is stuck?

Typically, only the pressure control solenoid (or the valve‑body assembly that contains it) needs replacement; a full transmission replacement is rarely required.

Is it safe to drive with P0747?

The vehicle may enter a fail‑safe mode limiting gear selection, and prolonged operation can lead to transmission damage, so the issue should be diagnosed and repaired promptly.