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O/D Main Switch & O/D Off Indicator Light Circuit

O/D Main Switch & O/D OFF Indicator Light Circuit

CIRCUIT DESCRIPTION
The O/D main switch contacts go off when the switch is pushed in and come on when it is pushed out. In O/D main switch OFF position, the O/D OFF indicator lights up, and the ECM prohibits shifting to overdrive. The ECM also causes the O/D OFF indicator light to blink when a malfunction is detected. In this case, connecting the OBD-II scan tool or TOYOTA hand-held tester to the DLC3 can display the diagnostic trouble code.

WIRING DIAGRAM





INSPECTION PROCEDURE
O/D OFF indicator light does not light up

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O/D OFF indicator light remains ON

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O/D OFF indicator light blinks
Perform diagnostic code check.
Displaying & Reading Trouble Codes