Throttle Position Sensor (TPS)

1. Install jumper wires to enable connection of a DVOM in parallel between TPS harness connectors. Connect DVOM positive lead to Dark Blue wire terminal. Connect negative lead to Black wire terminal. See Fig 1.
2. Turn ignition on, engine off. 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, adjust or replace TPS. See ADJUSTMENTS article in this section.
3. A malfunction in the TPS circuit should set a related trouble code. For further information, see appropriate article below:
   • TESTS W/CODES - DIESEL
   • TESTS W/CODES - GASOLINE
   • TESTS W/CODES - TRANSMISSION (If Transmission Codes Are Displayed)

Also refer to TPS adjustment procedure in ADJUSTMENTS article in this section.

Fig 1: Typical Throttle Position Sensor Circuit

Courtesy of GENERAL MOTORS CORP.