P0797 means pressure control solenoid C appears stuck on. Instead of modulating pressure, the circuit may be applying too much pressure or staying active when it should release.
What Stuck On Feels Like
A stuck-on pressure solenoid can create harsh shifts, firm engagement, bind-up, limp mode, or a transmission that feels like it is applying too much pressure. That is different from a stuck-off pressure code that often feels more like slipping.
Common Causes
- Solenoid C stuck mechanically from debris.
- Electrical or wiring issue holding the circuit active.
- Valve-body wear or contamination.
- Pressure regulator problem.
- Internal wear causing the computer to command pressure aggressively.
Diagnosis
We compare commanded solenoid state, pressure behavior, shift feel, fluid condition, and related codes. If the computer is commanding the solenoid off but pressure remains high, the mechanical/hydraulic side becomes the focus.
Can You Drive?
If shifts are violent or limp mode is active, call before driving. Harsh pressure events can damage mounts, axles, seals, and internal transmission parts.
Repair Path
P0797 may be solenoid, wiring, valve-body, or internal repair. The written estimate should explain whether the solenoid is the cause or a reaction to another pressure problem.
