P0733
AF23-5 AUTOMATIC TRANSAXLEDTC P0733
Test 1-11:
Test 12-21:
Test 22-28:
Circuit Description with AF23-5 Automatic Transaxle
The transmission control module (TCM) calculates gear ratio based on data from the transmission input shaft speed (ISS) and output shaft speed (OSS) sensors. The TCM compares the calculated gear ratio to the known gear ratio for each commanded gear.
If the TCM detects an incorrect 3rd gear ratio, indicating excessive slip or drag within the transmission, then DTC P0733 sets. DTC P0733 is a type A DTC.
Conditions for Running the DTC
^ No TR switch DTC P0705.
^ No TFT DTCs P0711, P0712, or P0713.
^ No ISS DTC P0717.
^ No OSS DTC P0722.
^ No engine speed DTC P0727.
^ No TCC DTC P0741.
^ No solenoid DTCs P0962, P0963, P0966, P0967, P0970, P0971, P0973, P0974, P0976, P0977, P0979, P0980, P0982, P0983, P0985, or P0986.
^ No engine torque DTC P1781.
^ No throttle position DTC P1791.
^ No CAN DTCs U2104 or U2105.
^ The brake switch is released.
^ The ignition voltage is 10.5-18 volts.
^ The transmission temperature is greater than 20°C (68°F).
^ The transmission is in a forward range.
^ The elapsed time since the most recent range change is 8 seconds or greater.
^ The throttle position (TP) is 10 percent or greater.
^ The engine speed is at least 400 RPM.
^ The commanded gear has been 3rd for 0.5 seconds or greater.
^ The transmission output shaft speed (OSS) is 500 RPM or greater.
Conditions for Setting the DTC
The TCM commands 3rd gear and the actual gear ratio is not within 1.52:1-2.26:1 for 12 seconds.
Action Taken When the DTC Sets
^ The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL).
^ The TCM turns the Trans. Protection Mode ON. When the Trans. Protection Mode is ON, the following conditions occur:
- The transmission will operate in 5th gear when the transmission is shifted into D or I range and 2nd gear when shifted into L range.
- The line pressure is at maximum.
- The torque converter clutch (TCC) is disabled.
- The TCM freezes the transmission adaptive functions.
^ The TCM requests the ECM to limit engine torque to 150 Nm (111 ft. lbs.).
^ 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 P0733 in TCM history.
Conditions for Clearing the MIL/DTC
^ The ECM turns off the MIL after the third consecutive drive trip in which the TCM does not send a MIL illumination request.
^ A scan tool can clear the DTC.
^ The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an 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, or exceeding the trailer towing limit.
Test Description
The numbers refer to the step numbers on the diagnostic table.
5. This step determines that shift solenoid 2 or the M2 shift valve is stuck if the 3rd gear ratio is 1.45:1.
6. This step determines that shift solenoid 4 or the U1 shift valve is stuck if the 3rd gear ratio is 2.89:1.
7. This step determines if the output shaft speed sensor signal is skewed by a large factor.
8. This step determines if the input shaft speed sensor signal is skewed by a large factor.