AF23-5 Automatic Transaxle
AF23-5 AUTOMATIC TRANSAXLEDTC P0727
Test 1-3:
Test 4-10:
Circuit Description with AF23-5 Automatic Transaxle
Engine speed information is sent to the transmission control module (TCM) by the engine control module (ECM) through a communication network called the controller area network (CAN). Two circuits are used to communicate CAN data between the ECM and TCM. A fault in the CAN will not cause DTC P0727 to set by itself. If a CAN fault occurs, other DTCs will set before DTC P0727.
When the ECM sends the TCM an invalid engine speed, then DTC: P0727 will set. DTC P0727 is a type A DTC.
Conditions for Running the DTC
^ No CAN DTC U2105.
^ The system voltage is 8-18 volts.
^ Trans. Protection Mode is OFF.
^ The ignition has been ON for at least 3.0 seconds.
Conditions for Setting the DTC
The engine speed is invalid for 4.0 seconds.
Action Taken When the DTC Sets
^ The TCM illuminates the malfunction indicator lamp (MIL).
^ The TCM turns Trans. Protection Mode ON. When Trans. Protection Mode is ON, the line pressure is at maximum, and updates to the transmission adaptive pressure (TAP) memory cells are discontinued. The transmission will operate in 5th gear.
^ Limit engine torque to 270 Nm (200 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 ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as a Freeze Frame.
^ The TCM stores DTC P0727 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 MIL/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 default actions when the ignition is OFF long enough in order to power down the TCM.