P0963Pressure Control Solenoid A Control Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- Pressure control solenoid A circuit high: the driver detects a short to voltage, and on GM's six-speeds also an open circuit, since those units have no separate open code. The Saab 9-4X 6T70 (line pressure solenoid) sets it after 5 s as Type B, GM's 2018 table after 4.4 of 5 s over two trips; the module then commands maximum line pressure and freezes adaptations. Ford tests its line pressure (EPC) solenoid for short to power and, in some applications, keeps P0963 like P0960 without MIL because maximum line pressure does not raise emissions. GM's 8-, 9- and 10-speeds and Allison 1000 (power short within 75 ms) use A for a clutch or main modulation solenoid. Expect firm, harsh shifts rather than slipping. Siblings: P0960, P0961, P0962.
- What you may notice
- Firm or harsh shifts at maximum line pressure
- Warning light, on some vehicles only after two drives or not at all
- Shift adaptation no longer improves
- Likely causes
- LikelyOpen coil or high-resistance connection (reported as high on GM six-speeds)
- PossibleControl wire shorted to a supply voltage
- PossibleDamaged or contaminated connector at the transmission
- RareFaulty output 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: €150 – €1,800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.