P097BShift Solenoid B Control Circuit/Open
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Open-circuit fault in the drive circuit of shift solenoid B. Public use is again limited to GM's Allison 1000 six-speed in heavy-duty trucks, where the 2022 to 2025 tables label it Shift Solenoid 2 Control Circuit Open. SS2 shares high-side driver 2 with SS1 and SS3, so the open test only runs while that supply is on and free of P2669, P2670 or P2671. It confirms an open by switching the low-side driver off and needs three samples, 120 ms, MIL after one trip. Allison's 2007 table filed the same check as P0975, the 2016 table under P0976. Ford reports an open SSB as P0755, GM six-speeds as P0977. Low/high are P0976/P0977.
- What you may notice
- MIL on after one faulty trip
- Default gear operation, some ranges unavailable
- Harsh or missing shifts
- Likely causes
- LikelyOpen coil of shift solenoid 2/B
- LikelyLoose or corroded terminal on the solenoid B circuit
- PossibleWire broken by vibration or heat near the transmission
- RareFaulty driver stage in the control module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €100 – €1,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.