Advanced Diagnostics

DTC P0734: Problem in 4th Clutch and 4th Clutch Hydraulic Circuit

General Description
To transmit the 4th gear driving force, line pressure is supplied to the 4th clutch piston, the 4th clutch is engaged, and the mainshaft and the mainshaft 4th gear are connected and revolve together. Hydraulic pressure is supplied to the 4th clutch through the ATF strainer the ATF pump the regulator valve the manual valve the shift valves the feed pipe 4th clutch piston. (The shift valve failure in the supplying route above is detected by the malfunction detection of each shift solenoid valve.) The powertrain control module (PCM) computes the ratio of the mainshaft speed to the countershaft speed. When the ratio is not the 4th gear ratio, it is detected as a malfunction of the hydraulic circuit or the 4th clutch, and a DTC is stored.




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




Enable Conditions

Malfunction Threshold
The actual gear ratio must match one of these conditions for at least 12 seconds with the 4th gear command:
- Actual gear ratio less than 4th gear ratio by a factor of 1.2
- Actual gear ratio greater than 4th gear ratio by a factor of 0.75

Driving Pattern
Start the engine, shift to D position, and drive the vehicle at a speed of 8 mph (12 km/h) or more for at least 12 seconds in 4th gear.

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

Diagnosis Details

Conditions for illuminating the indicator
When a malfunction is detected, the D indicator blinks, and the DTC and the freeze frame data are stored in the PCM memory. The MIL does not come on.

Conditions for clearing the DTC
The DTC and the freeze frame data can be cleared by using the scan tool Clear command or by disconnecting the battery.