P0735

DTC P0735

Test 1-8:

Test 9-14:

Circuit Description
The TCM calculates gear ratio based on data from the automatic transmission input shaft speed and output shaft speed sensors. The TCM compares the known transmission gear ratio to a calculated ratio for each commanded gear.

If the TCM detects an incorrect 5th gear ratio, indicating excessive slip or drag within the transmission, then DTC P0735 sets. DTC P0735 is a type C DTC.

Conditions for Running the DTC
^ No throttle system DTC P0120.
^ No ISS DTCs P0716 or P0717.
^ No OSS DTCs P0722 or P0723.
^ No IMS DTCs P1815, P1820, P1822, P1823, P1825 or P1826.
^ The engine run time is greater than 5 seconds.
^ The transmission is not in PARK or NEUTRAL.
^ The elapsed time since the most recent range change is greater than 6 seconds.
^ The transmission fluid temperature is 20 - 130°C (68 - 266°F).
^ The engine torque is greater than 55 Nm (41 ft. lbs.).
^ The throttle position is 10 percent or more.
^ The gear ratio is between 0.61:1 and 4.14:1.
^ The gear ratio is not Reverse: 3.1:1 to 2.95:1.
^ The vehicle speed is greater than 5 km/h (3 mph).

Conditions for Setting the DTC
The TCM commands 5th gear and the gear ratio is not within one of the following ranges for 4 seconds:
^ The gear ratio is not within 3.76:1 to 3.33:1
^ The gear ratio is not within 2.44:1 to 2.10:1
^ The gear ratio is not within 1.76:1 to 1.44:1
^ The gear ratio is not within 1.10:1 to 0.90:1
^ The gear ratio is not within 0.83:1 to 0.68:1

Action Taken When the DTC Sets
^ The TCM does not request the ECM to illuminate the Malfunction Indicator Lamp (MIL).
^ SERVICE VEHICLE SOON displays on the Driver Information Center (DIC).
^ The TCM commands maximum line pressure.
^ The TCM freezes transmission adaptive functions.
^ The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as a Failure Record.
^ The TCM stores DTC P0735 in TCM history.

Conditions for Clearing the DIC/DTC
^ The TCM clears the DIC message when the condition no longer exists.
^ A scan tool can clear the DTC.
^ The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non emission related diagnostic fault occurring.
^ The TCM cancels the DTC default actions when the ignition is OFF long enough in order to power down the TCM.

Diagnostic Aids
Ask the customer about overloading the vehicle, exceeding the trailer towing limit, or towing in Overdrive.

Test Description
The numbers below refer to the step numbers on the diagnostic table.
3. This step tests for low fluid level, which may cause slipping, and result in an incorrect gear ratio.
4. This step verifies that the correct 5th gear ratio occurs for commanded 5th gear. If necessary, use the Shift Transmission function of the scan tool in order to command 5th gear for the length of time necessary to read the gear ratio from the display.
5. This step tests for low line pressure.