Code P0122, Throttle Position Sensor: Notes

The Throttle Position (TP) sensor provides a voltage signal that changes relative to throttle blade angle. Signal voltage will vary from .20-.74 volt at idle to greater than 4 volts at Wide Open Throttle (WOT). TP sensor signal is one of the most important inputs used by PCM for fuel control and for most of the PCM control outputs.

With Code P0122 set, Tech 1 will continue to display the actual throttle sensor voltage, but ignore TP signal and read mass air flow value for other PCM controlled functions, PCM will not allow 4th gear, TCC or cruise control operation, 1st, 2nd, and 3rd allowed. PCM will illuminate Malfunction Indicator Light (MIL).

1. Determines if conditions necessary to set Code P0122 exist.
2. Simulates Code P0123 (high voltage). If PCM recognizes high signal voltage and sets Code P0123, PCM and wiring are okay.
3. Simulates a high signal voltage. Checks signal circuit for an open.