Code U0683 indicates the powertrain control module has lost communication with the throttle pedal position sensor/switch F circuit. This typically involves a redundant pedal position track or sub-sensor used to verify accelerator input. The PCM sets this code when it no longer receives an expected signal or message from that specific pedal sensor path.
The accelerator pedal position sensor itself is the most common cause, especially if one internal track fails while another remains active.
Corroded, bent, pushed-out, or loose terminals and damaged harness wiring can interrupt the signal between the pedal sensor and the PCM.
A blown fuse, poor ground, or missing 5-volt reference supply can prevent the pedal sensor from communicating properly.
An open, short, or splice problem on the communication bus between the pedal sensor/module and the PCM can cause a lost-communication code.
Rare; a failed driver or internal communication fault in the PCM is possible but should only be considered after all sensor and wiring checks pass.
Usually not. This code is most often caused by the pedal position sensor, its wiring, or a power/ground issue. Replacing the PCM is rarely the correct fix and should only be done after all other checks are complete.
It is not recommended. The vehicle may enter limp mode or lose throttle response, which can be unsafe. Have it diagnosed promptly.
It refers to a specific track or sub-circuit of the throttle pedal position sensor. Many vehicles use multiple redundant pedal sensor tracks so the PCM can detect disagreements for safety.
It often will if the sensor has failed, but wiring, connector, and power/ground problems should be verified first to avoid replacing a good sensor.