Throttle Position Sensor: Testing and Inspection

INSPECTION

1. Turn ignition switch off. Disconnect the three pin connector at the Throttle Position Sensor (TPS). Turn ignition switch on.

Throttle Position Sensor Connector Terminal Identification.:

PGM-FI ECM Connector Description And Wire Location:

2. Measure voltage between YELLOW/WHITE (+) terminal and GREEN/WHITE (-) terminal. Voltage should read approx 5.0 volts. If not, measure voltage between YELLOW/WHITE (+) terminal and chassis ground;
^ If 5.0 volts is measured check for open in GREEN/WHITE (-) wire between Programmed Fuel Injection Electronic Control Module (PGM-FI ECM) D22 and TPS connector.
^ If 5.0 volts is not measured, Turn ignition switch off, install test harness between PGM-FI ECM and harness connector, turn ignition on. measure voltage between terminal D20 (+) and D22 (-), if 5.0 volts is measured, inspect for open in YELLOW/WHITE wire between D20 and TPS connector. If 5.0 volts is not measured, substitute known good PGM-FI ECM and retest.
3. Turn ignition switch off. Reconnect the three pin connector at the TPS. Install the test harness between the PGM-FI ECM and the harness connector. Turn ignition switch on.
4. Measure voltage between terminal D11 (+) and terminal D22 (-). Voltage should read approx. 0.5 volts at closed throttle position and approx. 4.5 volts at full throttle position with a smooth transition in between. If not, replace TPS with known good part and retest.