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P1791

DTC P1791: Throttle Position Input Signal Circuit Malfunction





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.

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

Conditions for Setting the DTC
^ System voltage is too high or too low.
^ TCM or ECM is defective.
^ Immediately after the above condition occurs.

Action Taken When the DTC Sets
^ No lamp control required but diagnostic information should be stored immediately when malfunction is detected.
^ Adjustable value, calculated over the substitute map throttle position. (engine speed, engine torque)

Conditions for Clearing the MIL/DTC
Using a scan tool can clear history DTCs.

Diagnostic Aids
^ Inspect the poor wiring harness connection for TCM connectors and transaxle wiring connectors.
^ Inspect the improperly formed or damaged terminals.

Troubleshooting