Code 22, TPS Signal Low: Notes
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The Throttle Position Sensor (TPS) provides a voltage signal that changes relative to throttle valve angle. Signal voltage will vary from less than about 1.25 volts at idle to about 4.5 volts at wide open throttle.
NOTE:
Test numbers refer to test numbers on diagnostic chart.
- This test confirms Code 22 and tests if the fault is because of a hard failure or an intermittent condition. Code 22 will set if engine is running, TPS voltage is less than .2 volt for 2 seconds.
- This simulates Code 21. If the ECM recognizes a high voltage signal and sets Code 21, the ECM and wiring are not at fault.
- This checks for voltage to the ECM. If the ECM recognizes the voltage as over 4 volts, the ECM and TPS signal circuit are not at fault.
- If 5-volt reference circuit is open or shorted to ground, there may also be a Code 34 stored.