Throttle Position Sensor: Testing and Inspection

TPS Schematic:

To test the Throttle Position Sensor, located on the throttle body, proceed as follows.


1. Disconnect the throttle position sensor connector.

TPS Testing:

2. Measure the resistance between terminals 4 and 8 of the throttle position sensor connector.
Terminal 8: Sensor ground
Terminal 4: Sensor power

Standard Value...3.5-6.5 Kohm



3. Connect an analog type ohmmeter between terminals 8 and 3.
Terminal 8: Sensor ground
Terminal 3: Sensor output

4. Slowly open the throttle valve from the idle position to the fully open position and check that the resistance values change smoothly with the opening of the throttle valve.
Standard Value...Approx 0.5 Kohm increasing to 3.5-6.5 Kohm

5. If the resistance is out of specification, or if the change is not smooth, replace the throttle position sensor.


HARNESS TEST

1. Disconnect the TPS connector and Turn on the ignition.

2. Using a voltmeter, measure the supply voltage between the TPS harness connector terminal 4 and ground.

Voltage: 4.8 - 5.2 Volts.

3. Check for continuity between the TPS harness connector terminal 8 and ground.

Continuity: Should Exist.

4. Turn off the ignition and disconnect the ECU connector. Check for continuity (short) to ground, between the ECU harness connector terminal 13 and the TPS harness connector terminal 3.

Continuity: Should Not Exist.

5. Check for continuity between the ECU harness connector terminal 13 and the TPS harness connector terminal 3.

Continuity: Should Exist.



If any of the previous tests produce unsatisfactory results, the harness will need to be repaired or replaced. Once repairs have been completed, road test the vehicle to confirm that the repair has corrected the problem.

If the same trouble reoccurs, it is possible that there is an intermittent failure of the component or the ECU. Check for looseness at all harness junctions, and test for an intermittent failure.