What P0796 means
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.
How the engine computer detects it
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.
Written from public technical sources and not yet checked by a mechanic. How we write these pages
Symptoms
- Slipping or missing upper gears
- Limp mode
- Check engine light
Common causes
- Clutch, return spring or piston seal of the assigned clutch faulty Most likely
- Valve body or pressure valve dirty or worn Most likely
- Fluid level low, fluid worn, filter clogged Possible
- Software false setting Possible
How to diagnose P0796
- Read every stored code with an OBD-II scanner. If misfire or fuel trim codes are there too, fix those first: they often cause this one.
- Inspect the parts involved: pressure control solenoid, transmission valve body, transmission clutches, transmission control module.
- Work through the causes above from most to least likely, cheapest checks first.
- Clear the code and drive a full drive cycle to confirm the repair held.
Vehicles that report P0796 most
| Vehicle | Years | Reports | Share | Median miles |
|---|---|---|---|---|
| Chevrolet Silverado 1500 | 2016–2017 | 5 | — | |
| Chevrolet Tahoe | 2017–2019 | 3 | — | |
| Chevrolet Suburban | 2015–2016 | 3 | — |
Counts of owner complaints to the NHTSA that mention P0796 (22 in total), not failure rates: popular models get more complaints simply because more of them are on the road. Models with fewer than 3 complaints are left out.
Reading the code
- P
- Powertrain
- 0
- Generic (SAE) code
- 7
- Transmission
- 96
- Specific fault
Questions drivers ask
Can I drive with code P0796?
Drive gently and only as far as you need to. The engine computer may limit power to protect the engine, so avoid highways and heavy traffic until it's fixed. If the check engine light starts flashing, pull over.
Will my car pass an emissions inspection with P0796?
Probably not in states that test vehicles with an OBD-II scan: an emissions-related code that keeps the check engine light on is usually an automatic fail. Rules differ by state and county, so check yours.
Often reported together
Codes that owners mention in the same NHTSA complaints as P0796. They can point to a shared cause, so it's worth checking them together.
This page is general information, not a substitute for a professional diagnosis. Repair costs are rough estimates for parts and labor and vary by vehicle and region.