DTC 22

DTC 22 - Throttle Position (TP) Sensor Circuit (Signal Voltage Low):

Throttle Position (TP) Sensor Wiring Circuit:

Circuit Description:

The Throttle Position (TP) sensor provides a voltage signal that changes relative to the throttle blade. Signal voltage will vary from about .5 at idle to about 4.5 volts at Wide Open Throttle (WOT).

The TP sensor signal is one of the most important inputs used by the ECM for fuel control and for most of the ECM control outputs.

Test Description: Number(s) below refer to circled number(s) on the diagnostic chart.

1. DTC 22 will set if:
^ Engine is running.
^ TP sensor signal voltage is less than about .2 volt.
2. Simulates DTC 21: (high voltage) If the ECM recognizes the high signal voltage then the ECM and wiring are OK.
3. TP sensor check. The TP sensor has an "Auto Zeroing" feature. This means that the ECM has the ability to auto-zero the TP sensor voltage if it is below about 1.25 volts at idle. The ECM will use this value to be 0% throttle. The TP sensor is not adjustable. If the TP sensor voltage is out of the "Auto Zeroing Range," check for binding or sticking cruise control or throttle cables. If OK, replace the TP sensor.
4. This simulates a high signal voltage to check for an open CKT 417.

Diagnostic Aids:

A Tech 1 scan tool reads throttle position in volts. Should read less than 1.25 volts with throttle closed and ignition "ON" or at idle. Voltage should increase at a steady rate as throttle is moved toward Wide Open Throttle (WOT). Tech 1 will also display throttle angle. Key "ON" engine "OFF" Tech 1 will display less than 100% at Wide Open Throttle (WOT).

An open or short to ground in CKT 416 or CKT 417 will result in a DTC 22.

- Intermittent Malfunctions