What it means
Pressure Control Solenoid C Performance: the component is electrically intact but its response does not match the command. It regulates transmission line pressure; faults cause slipping, harsh, or delayed shifts.
At a glance
- Usually lights the check-engine light
- The engine or gearbox may go into limp mode
How it works
Pressure control solenoid C adjusts hydraulic pressure in a transmission circuit in response to TCM commands. P0796 sets when the electrical circuit appears intact but the observed pressure or shift response does not match what the TCM expects from solenoid C.
Common causes
Most likely first.
- Pressure Control Solenoid C sticking or binding
- Contaminated or degraded transmission fluid
- Restricted hydraulic passage or valve body
- Internal transmission wear or leakage
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
How to diagnose it
- Review freeze-frame data and live data for solenoid C commands, pressure feedback, and the gear changes or conditions when the response diverged.
- Check the transmission fluid level and condition by the vehicle's specified procedure, and inspect for leaks or degraded fluid.
- Inspect solenoid C's connector and harness for contamination, damage, poor terminal contact, or fluid intrusion that could affect control.
- Test solenoid C operation and compare its response with TCM commands using the manufacturer's procedure.
- If solenoid C responds correctly, check for restricted hydraulic passages, valve body problems, or internal pressure loss affecting the circuit it controls.
Common fixes
- Correct a low fluid level or leak, and service degraded fluid only as specified for the vehicle.
- Repair poor connections or damaged wiring at pressure control solenoid C.
- Replace solenoid C if it sticks or fails to respond correctly during testing.
- Clean or repair a restricted valve body passage or address confirmed internal leakage.
Can I keep driving?
Avoid towing, hard acceleration, and continued driving with slipping or delayed shifts; the TCM may limit operation and friction parts can overheat. If the transmission cannot hold a gear or loses drive, stop safely and arrange service.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.