Advanced Diagnostics

Advanced Diagnostics

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









General Description
Shift valve E is in the control circuit of the transmission. It is controlled by pressure from shift solenoid valve B, and it is locked by 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, and the gear change is determined by the shift schedule. When an improper gear ratio output is 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 for at least 2 seconds.
- After driving the vehicle in 3rd gear for at least 2 seconds.

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

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

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, a Confirmed DTC and the freeze data are stored. The MIL does not come on.

Conditions for clearing the DTC
The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.