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Overdrive Switch: Testing and Inspection







DIAGNOSIS AND TESTING - OVERDRIVE ELECTRICAL CONTROLS

The tow/haul overdrive off switch, valve body solenoid, case connectors and related wiring can all be tested with a 12 volt test lamp or a volt/ohmmeter. Check continuity of each component when diagnosis indicates this is necessary.

Switch and solenoid continuity should be checked whenever the transmission fails to shift into fourth gear range.