Pressure control solenoids are current-controlled proportional valves, and what B and C mean depends on the design: on GM's clutch-to-clutch automatics they are the pressure valves of clutches 2 and 3, on GM's CVT B is primary pulley pressure and C line pressure, on Jatco CVTs B is the secondary pressure valve, on Saab's AF40 B and C are clutch valves SLC1/SLC2. P0796 means valve C is electrically fine but pressure stays too low. GM's 6-speed flags 400 rpm slip in steady fourth gear with an intrusive test (4-5-6 clutch), the 8-speed 400 rpm for 1.5 s three times (clutch 3), the 9-speed clutch 3 slip over 200 rpm for 3 s, the CVT a line pressure deviation – all after one trip. GM noted false settings on 2017 8-speeds; a 9-speed bulletin calls for clutch inspection and a new valve body. Slipping, missing upper gears and limp mode follow.
Medium severity. Can I keep driving?Drive as little as possible and gently. If the transmission slips or stays in one gear, go slowly to a repair shop or call for a tow truck.
Symptoms
- Slipping or missing upper gears
- Limp mode
- Check engine light
Most likely causes
- Clutch, return spring or piston seal of the assigned clutch faulty
- Valve body or pressure valve dirty or worn
- Fluid level low, fluid worn, filter clogged
- Software false setting
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: hard
- It can trigger limp mode.
- It affects emissions.
What each character of P0796 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 7: Transmission
- 96: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0796?
Drive as little as possible and gently. If the transmission slips or stays in one gear, go slowly to a repair shop or call for a tow truck.
What causes code P0796?
The most common causes are: clutch, return spring or piston seal of the assigned clutch faulty; valve body or pressure valve dirty or worn; fluid level low, fluid worn, filter clogged.
Related codes
- P0795Pressure Control Solenoid C
- P0797Pressure Control Solenoid C Stuck On
- P0798Pressure Control Solenoid C Electrical
- P0776Pressure Control Solenoid B Performance/Stuck Off
- P0746Pressure Control Solenoid A Performance/Stuck Off
- P0969Pressure Control Solenoid C Control Circuit Range/Performance
Sources
- gsi.ext.gm.com: 19OBDG03B Diagnostics
- gsi.ext.gm.com: 19OBDG03C Diagnostics
- gsi.ext.gm.com: 20OBDG03A Diagnostics
- gsi.ext.gm.com: 25OBDG03A
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.