U0606 indicates that the engine control module (PCM) has lost communication with the throttle pedal position sensor (or sensor switch). This typically points to an electrical fault in the sensor circuit, such as a damaged wire, poor connection, or a failing sensor itself.
The sensor itself has failed internally, causing loss of signal to the PCM. This is the most common root cause.
Open circuits, shorts to ground, or corrosion in the sensor harness or connector can interrupt communication.
On some vehicles the pedal position sensor is part of the throttle body assembly; a failing throttle body can cause the same code.
Insufficient voltage (below 12.4V) can disrupt sensor communication and trigger U0606.
PCM internal faults are rare but possible if all other components and wiring test good. This is the least likely cause.
You may be able to drive, but the vehicle will likely enter limp mode with reduced power. It is not safe to drive if the throttle response is unpredictable or the engine stalls. Have it diagnosed promptly.
No. While the sensor is a common failure, wiring issues, connector corrosion, or even a weak battery can cause the same code. Always inspect the circuit thoroughly before replacing parts.
Almost never. The PCM is rarely the cause of this code. Replacing the PCM without verifying all wiring and the sensor is a common misdiagnosis. Only consider it after all other possibilities have been ruled out.
Yes. Low battery voltage (below 12.4V) or a failing charging system can disrupt communication between the PCM and the throttle pedal sensor, triggering this code. Always check battery health first.