P0727

DTC P0727: Engine Speed Input Circuit No Signal





Circuit Description
The Transaxle Control Module (TCM) is an electronic device which monitors inputs to control various transaxle functions including shift quality and transaxle sensors, switches, and components to process for use within its control program. Based on this input information, the TCM controls various transaxle output functions and devices.

DTCs P0725, P0726 and P0727 are related to the same circuit. These DTCs will not illuminate the MIL, however, the DTC will be stored in memory.

Information transmit between TCM and ECM through the CAN line. information is as follows:
^ Engine Malfunction Signal
^ Engine Speed
^ Engine Output Torque Reduction Signal
^ Engine Coolant Temperature

Conditions for Setting the DTC
^ When turbine speed is more than 1,500 rpm, engine speed is less than 400 rpm.
^ System voltage is too high or too low.
^ CAN transmitting wiring harness shorted or open.
^ TCM or ECM is defective.
^ Immediately after the above condition occurs.

Action Taken When the DTC Sets
^ Hold lamp will blink.
^ The TCM will record operating conditions at the time the diagnostic fails. This information will be stored in the Failure Records buffer.
^ Adopt Emergency/Substitute mode and constant 4th gear.
^ Open lock up clutch.

Conditions for Clearing the MIL/DTC
^ The hold lamp will turn OFF when the malfunction has not occurred after three-ignition cycles.
^ A history DTC will clear after 40 consecutive warm up cycles without a fault. 0 Using a scan tool can clear history DTCs.

Troubleshooting