Advanced Diagnostics

DTC P0751: Shift Solenoid Valve A Stuck OFF

General Description
Shift solenoid valve A is installed in the transmission housing. It is controlled by the ON/OFF signal from the powertrain control module (PCM), to apply modulated pressure to shift valve A. The signal from the PCM is output to apply clutch pressure control pressure to the proper gear change clutch according to the gear change schedule. When the signal to shift solenoid valve A from the PCM is ON, and modulated pressure is discharged, shift valve A is inactive. When the signal to shift solenoid valve A from the PCM is OFF, and modulated pressure is applied to shift valve A, it operates against the shift valve A spring. The PCM monitors the mainshaft speed and the countershaft speed at the gear change determined by the shift schedule. When an improper gear ratio is output compared to the predetermined gear change mode, a shift solenoid valve A OFF failure is detected and a DTC is stored.




Monitor Execution, Sequence, Duration, DTC Type, OBD Status




Enable Conditions

Malfunction Threshold

Case 1
The transmission is held in 3rd gear against the 1st -to 2nd gear upshift command for 20 seconds or less.

Case 2
The transmission is held in 4th gear against the 4th -to 5th gear upshift command for 20 seconds or less without a record that he gear change time was short when the 3rd -to 4th gear upshift was commanded.

Driving Pattern
Start the engine, and accelerate the vehicle until the transmission shifts into 5th gear in the D position.

- Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.

Diagnosis Details

Conditions for illuminating the MIL
When a malfunction is detected during the first drive cycle, a Temporary DTC is stored in the PCM memory. If the malfunction recurs during the next (second) drive cycle, the MIL comes on and the DTC and the freeze frame data are stored.

Conditions for clearing the MIL
The MIL will be cleared if the malfunction does not recur during three consecutive trips in which the diagnostic runs.

The MIL, the DTC, the Temporary DTC, and the freeze frame data can be cleared by using the scan tool Clear command or by disconnecting the battery.