Faulty Accelerator Pedal Position (APP) Sensor
Accelerator Pedal Position (APP) Sensor harness is open or shorted
Accelerator Pedal Position (APP) Sensor circuit poor electrical connection
Engine Light ON (or Service Engine Soon Warning Light)
Sensor Supply Voltage Circuit ‘C’ Malfunction is the generic description for the P1646 Acura code, but the manufacturer may have a different description for your model and year vehicle. Currently, we have no further information
about the P1646 Acura OBDII code.