Advanced Diagnostics

DTC P1744: Problem in Shift Control System; Shift Valve E Stuck ON







General Description
Shift valve E is incorporated in the control circuit of the transmission. It is controlled by pressure from shift solenoid valve B, and it is locked by the line pressure. It switches off when shift solenoid valve B turns off and shift solenoid valve A turns on. 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 valve E ON failure is detected and a DTC is stored.




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




Enable Conditions

Malfunction Threshold
The transmission is held in 5th gear against the 1st gear shift command after driving the vehicle in 3rd gear in the D position for at least 1.5 seconds.

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 DTC and the freeze frame data are stored. The MIL does not come on.

Conditions for clearing 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.