O/D Main Switch
WARNING: This page is about a different car, the 2002 Toyota Avalon and 2001 Toyota Avalon. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
For circuit reference, see WIRING DIAGRAMS and/or CONNECTOR IDENTIFICATION
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- Check O/D OFF indicator for proper operation. O/D OFF indicator should illuminate when O/D main switch is depressed (ON position), and go off when released (OFF position). If O/D OFF indicator is not okay, go to next step. If O/D OFF indicator is okay and you were directed here for a no 3-4 upshift, see O/D CANCEL SIGNAL . If O/D OFF indicator is okay and you were directed here for any other symptom, substitute ECM with known-good unit and retest.
- Remove instrument cluster and check O/D OFF indicator circuits and bulb. Repair or replace instrument cluster as needed. If instrument cluster O/D OFF indicator circuits and bulb are okay, go to next step.
- Turn the ignition to the OFF position. Disconnect the O/D main switch 4-pin connector. Check for continuity between O/D main switch connector terminals No. 2 and 4. See Fig 1. Continuity should not exist with O/D main switch released, and should exist with O/D main switch depressed. If continuity is as specified, go to next step. If continuity is not as specified, replace O/D main switch.
- Turn the ignition to the ON position. Access the ECM. See Figure. Using DVOM, measure voltage by backprobing between ECM 17-pin connector E6 terminal No. 12 and ground. See Figure. Voltage should be less than one volt with O/D main switch depressed, and 10-14 volts with O/D main switch released. If voltage is not as specified, go to next step. If voltage is as specified, replace ECM and retest. See appropriate REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE.
- Turn the ignition to the OFF position. Disconnect the ECM 22-pin connector E8. Turn the ignition to the ON position. Using DVOM, measure voltage between ECM connector E8 terminal No. 9 and ground. If voltage is 7.5-14 volts, replace ECM and retest. If voltage is not 7.5-14 volts, check and repair circuit as necessary between instrument cluster and ECM, O/D main switch and ECM, or between O/D main switch and ground.