Transmission

P0796 — Pressure Control Solenoid C Performance or Stuck Off

Severity: medium Drive with care, to a shop

What P0796 means

The transmission control module regulates hydraulic pressure in the valve body using pressure control solenoids. P0796 means solenoid C is performing poorly or is stuck off, so actual pressure in its circuit does not match the commanded value. Clutches then apply with too little force, causing weak or slipping shifts.

Symptoms

  • Weak or delayed shifts
  • Slipping during acceleration
  • Harsh or flaring shifts
  • Check Engine or transmission warning light on
  • Transmission in limp mode
  • Worse fuel economy

Possible causes

  1. Failed or stuck pressure control solenoid C
  2. Debris or wear material in the valve body
  3. Worn transmission pump
  4. Damaged wiring or poor connector contact
  5. Faulty TFP solenoid or pressure sensor
  6. Low or degraded transmission fluid
  7. TCM or PCM fault (uncommon)

How to diagnose

  1. Scan all codes and freeze frame data and look for other transmission codes
  2. Check transmission fluid level and condition: color, smell, metal particles
  3. Inspect the transmission connector and harness for corrosion, breaks and chafing
  4. Measure solenoid C resistance and compare it to the service manual spec
  5. Check power and ground on the solenoid circuit
  6. Use a scan tool to compare commanded and actual pressure during tests
  7. Drop the pan and inspect the magnet and filter for debris
  8. If needed, remove the valve body and inspect valves and solenoids

Common fixes

  • Change transmission fluid and filter
  • Repair wiring or the connector
  • Replace pressure control solenoid C
  • Clean or overhaul the valve body
  • Replace the pump or rebuild the transmission if wear is severe

Questions and answers

What does P0796 mean?

The transmission control module found that pressure control solenoid C is not producing the target pressure or is stuck off. Common causes are the solenoid itself, valve body debris or wiring.

Can I drive with P0796?

Only a short distance to a shop. Slipping quickly overheats and wears the clutches, which can make the repair much more expensive.

Will a fluid change fix it?

Sometimes, if low or dirty fluid is the cause. If the solenoid or valve body is damaged, a repair will be needed.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.