DTC Advanced Diagnostics: P0797
DTC P0797 : CVT Clutch Pressure Control Solenoid Valve Stuck ON
General Description
The CVT clutch pressure control solenoid valve controls hydraulic pressure to the forward clutch and the reverse brake. The CVT clutch pressure control solenoid valve is controlled by duty cycle output. The spool in the CVT clutch pressure control solenoid valve moves the valve according to the current, and produces hydraulic pressure in proportion to the current. To supply proper forward clutch/reverse brake hydraulic pressure, the transmission control module (TCM) outputs a CVT clutch pressure control solenoid valve hydraulic pressure control signal. If the duration of the forward clutch/reverse brake engage operation from start to completion is short, the TCM detects a CVT clutch pressure control solenoid valve stuck ON failure and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous |
| Sequence | None |
| Duration | Depending on the driving conditions |
| DTC Type | Two drive cycles, MIL on, Shift position indicator blinks |
Enable Conditions
| Condition | Minimum | Maximum | |
|---|---|---|---|
| Engine speed [Engine Speed] | 500 rpm | - | |
| Vehicle speed [Vehicle Speed] | - | 1 mph (3 km/h) | |
| Accelerator pedal position | - | 0.6 deg. | |
| Shift position/mode | D, S | ||
[ ]: HDS Parameter
Malfunction Threshold
Forward clutch engagement when shifted from N position/mode to D position/mode takes less than 400 milliseconds.
Possible Cause
The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- CVT clutch pressure control solenoid valve stuck on
Confirmation Procedure
Operating Condition
- Start the engine.
- With the brake pedal pressed, place the shift from N position/mode to D position/mode, then shift to N position/mode, and wait for at least 2 seconds.
- Repeat Driving Pattern step 2, five times.
- Turn the vehicle to the OFF (LOCK) mode.
- Repeat Driving Pattern steps 1 through 3.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the TCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on, the shift position indicator blinks, and a Confirmed DTC and the freeze data are stored.
Conditions for clearing the DTC
The shift position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool clear command.