The Drive-By-Wire System (DBW) is controlled by the PCM, through a throttle drive motor and throttle position sensors. This sensor usually has a 5 volt supply, and a ground signal. The PCM uses the inputs from this sensor to control the throttle actuator motor, which is responsible for opening or closing the throttle plate, thus allowing air into the intake.
The factors for setting the P2109 OBD2 diagnostic code are:
TPS / PSS Sensor may be faulty.
The circuit between the Throttle Position Sensor / Pedal Position Sensor and the PCM could be open.
System circuit connectors may have excessive corrosion.
The DBW system motor could be in bad condition.
Possible solutions of the DTC code P2109 Generic
To troubleshoot the P2109 OBDII fault code you should do the following:
Consult the Technical Service Bulletins.
Check all electrical components of the system. Verify that the wires are not worn or burned, which can cause a short in the circuit. Check connector terminals for corrosion. Make repairs as required.
Inspect the throttle plate for excessive carbon buildup. Clean the plate if necessary.
With a multimeter, check the signal from the sensor wires related to the system. Operate the DBW system and check if the voltage changes when the throttle is moved from the closed to the open position. Compare the results obtained with the manufacturer's specifications. If you find inconsistencies in these values, the sensor is possibly defective.
Test the voltages of the circuits related to the system. Repair it as required.