P0727

DTC P0727

Circuit Description
Engine speed information is sent to the transmission control module (TCM) by the powertrain control module (PCM) through a communication network called the controller area network (CAN). Two circuits are used to communicate CAN data between the PCM 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 PCM sends the TCM an invalid engine speed, then DTC P0727 will set. DTC P0727 is a type A DTC.

DTC Descriptor
This diagnostic procedure supports the following DTC:

DTC P0727 Engine Speed No Signal

Conditions for Running the DTC
^ No CAN DTC U0100.
^ 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 requests the PCM to illuminate the malfunction indicator lamp (MIL).
^ The TCM turns Trans. Protection Mode ON.
^ 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.
^ 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 PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as a Freeze Frame.
^ The TCM stores DTC P0727 in TCM history.

Conditions for Clearing the MIL/DTC

Step 1 - Step 10:

^ The PCM 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.