Toyota Corolla (E120): Circuit description

The o/d main switch (transmission control switch) is a momentary type switch. When pressing the o/d main switch, the o/d off indicator light lights up and the ecm prohibits shifting into o/d, and when pressing it once again, the o/d off indicator light goes off and the ecm allows shifting into o/d. Turning the ig switch off will reset the o/d off indicator light.

Wiring diagram

Inspection procedure

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