What P0976 means
Low-voltage fault, normally a ground short, in the control circuit of shift solenoid B.
How the engine computer detects it
On GM six-speeds SS B is the mode 3 multiplex valve; the 2016 table sets P0976 after 1.2 of 1.5 s without lighting the MIL, while the Saab 9-4X 6T70 version needs 2 s, is Type B and raises line pressure. Ford uses it for SSB short to ground, with P0755 for an open; on the 2023 Super Duty diesel SSB is fed by solenoid supply TSPC2, so a P2669 supply fault disables this check. GM's Allison 1000 merges ground short and open into it in 2016, but from 2022 reports opens as P097B and keeps P0976 for ground faults found by an intrusive test (120 ms, MIL after one trip). High side is P0977.
Written from public technical sources and not yet checked by a mechanic. How we write these pages
Symptoms
- Warning light or stored code, on some GM six-speeds without MIL
- Firm shifts due to raised line pressure
- Gears missing or limp mode
Common causes
- Solenoid B control wire shorted to ground or housing Most likely
- Internal short in solenoid B or its valve body assembly Possible
- Moisture or debris bridging pins at the connector Possible
- Faulty driver in the transmission control module Less likely
How to diagnose P0976
- 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: shift solenoid b, wiring harness, tcm.
- 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.
Reading the code
- P
- Powertrain
- 0
- Generic (SAE) code
- 9
- Transmission
- 76
- Specific fault
Questions drivers ask
Can I drive with code P0976?
If the car shifts normally, drive gently to a shop. If it's stuck in one gear, slips, shifts harshly or won't move out of Park, don't drive it: have it towed.
Will my car pass an emissions inspection with P0976?
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.
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.