Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

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LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Overdrive Switch: Testing and Inspection

O/D SWITCH

OPERATION INSPECTION
1. Turn ignition switch ON.
2. Verify that the O/D indicator light is not illuminated.
Depress O/D switch and verify that the O/D indicator light illuminates.
3. If O/D indicator light does not operate, continue with inspection of voltage test.

VOLTAGE INSPECTION
1. Remove center panel.
2. Turn ignition switch ON.








3. Measure voltage at O/D switch connector.
B+: Battery positive voltage
4. If not as specified, check for continuity at O/D switch.
5. Install center panel.

CONTINUITY INSPECTION
1. Disconnect negative battery cable.
2. Disconnect O/D switch connector.








3. Check a continuity on 6 terminal and 7 terminal.
4. Replace selector lever knob if not as specified.
5. Check wiring harness for continuity if switch is operating correctly (from O/D switch to ECM, and from O/D switch to ground).