Operation CHARM: Car repair manuals for everyone.

Throttle Position Sensor: Testing and Inspection


NOTE:When testing the TPS, insert the tester leads through the back of the connector, ensure that the harness wires are not damaged by the test meter leads.
1. Turn key to ON position.
2. Unplug the TPS harness connector.
3. Measure voltage between connector terminal C and B of the TPS harness connector with a high impedence digital volt-ohmmeter.
Meter should show approx. 5 volts. If voltage is incorrect, test the vehicle using the DRB II tester.
4. Turn the ignition key to the OFF position.
5. Test for continuity between TPS connector pin B and ground using a high impedence digital volt-ohmmeter.
If the circuit is open, test the vehicle with the DRB II tester.
6. Reconnect TPS connector.
7. Turn key to On position.
8. Back probe TPS connector with a high impedence digital volt-meter (such as tool #C845 or an equivalent) and measure voltage from terminal A and ground.
Meter should register approx. 0.5 to 1.0 volts. If voltage is incorrect, attempt to adjust the TPS using the method in the Adjustments section of this group, or using the DRB II tester. If the sensor cannot be adjusted, the sensor is defective and should be replaced.