P0968: solenoid C open circuit can refer to CVT line-pressure control

P0968 is pressure-control solenoid C control circuit open. The cited table assigns C to different clutch circuits in eight-, nine- and ten-speed transmissions; in the CVT example it controls line pressure.

The monitored condition is electrical continuity

The controller compares circuit voltage with its calibrated limits, using an open-circuit detection specification above 200 kilohms between signal and controller ground. The code does not itself report line pressure, establish fluid starvation or identify a damaged clutch.

Failure must persist more than 0.3 second within a sample period exceeding half a second. The raw detection is updated every 6.25 milliseconds, but that update rate should not be mistaken for the complete DTC setting time.

A shared supply changes the diagnostic context

The solenoid's mapped high-side driver must be on. The table also requires battery voltage above 9 and below 32 volts for more than one second, with an allowed run/crank or accessory-power state. These are prerequisites for evaluating the controlled circuit, not optional details.

Confirm the transmission's C assignment and supply mapping before connecting the code to a symptom. A later absence of the fault with the supply off does not prove the open condition is repaired. Verification should establish a passing enabled electrical monitor and complete the appropriate operational checks. The table does not select a physical valve location or justify replacing a full transmission assembly.

Source and applicability

Documented monitors in gm-2025-03a, model year 2025. These are module/calibration examples; vehicle, engine and transmission applicability must be confirmed independently. GM 2025-03a, page 1151.