Throttle Position (TP) Sensor

Install jumper wires to enable connection of a DVOM in parallel between TP sensor harness connectors. Connect DVOM positive lead to Dark Blue wire terminal. Connect negative lead to Black wire terminal. See Fig 1 .
Turn ignition on, engine off. Slowly depress accelerator pedal. Signal voltage should gradually change from less than one volt at closed throttle to about 5.0 volts at wide open throttle position. If reading is not as specified, replace TP sensor.
TP sensor circuit malfunction should set a related trouble code. For further information, see TESTS W/CODES article. Also see TP SENSOR ADJUSTMENT in ADJUSTMENTS article.

Fig 1: Typical Throttle Position (TP) Sensor Circuit

Courtesy of GENERAL MOTORS CORP.