DTC 22

The Throttle Position Sensor (TPS) provides a voltage signal that changes relative to the throttle valve. Signal voltage will vary from less than 0.45 volts at idle to about 4.0 volts at wide open throttle (WOT).

The TPS signal is one of the most important inputs used by the ECM for fuel control and for many of the ECM controlled outputs.

Code 22 will set if:

^ TPS signal voltage is less than 0.2 volts.

Possible causes of Code 22:
^ Faulty TPS
^ Faulty wiring or terminals
^ Faulty ECM

1. Confirm Code 22, and that fault is present.
2. Simulates Code 21: If the ECM recognizes the high signal voltage and sets Code 21 the ECM and wiring are OK.
3. Check for reference voltage from the ECM. To prevent damage to ECM, be sure to disconnect ECM connector when checking circuit wiring for open or shorts to ground.