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Throttle Position Switch: Testing and Inspection

ECU Connector Pin Identification:






IDLE SWITCH CONTACT:

1. With ignition off, disconnect multiple pin plug from ECU.
2. Connect an ohmmeter across ECU connector terminals 3 and 5.
3. With throttle closed, correct resistance is 0 ohms.
4. With throttle opened, correct resistance is infinite. Switch from throttle closed to throttle open position. This should take place with a throttle gap of approximately 1°.

FULL LOAD (WOT) CONTACT:

1. Connect ohmmeter across ECU connector terminals 12 and 17.
2. With throttle closed, correct resistance value is infinite.
3. With throttle in full load position, correct resistance value is 0 ohms. Switch from throttle closed to full load position should take place at approximately 3/4 total throttle travel.
4. If test results are not as specified, check resistance values directly at switch.