1. Backprobe the rear defogger switch connector C1 between terminal B (Buick/Oldsmobile) or terminal 3 (Pontiac) and ground.
2. Press the rear defogger switch.

Does the test lamp illuminate?

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Go to Step 2

Go to Step 3

Replace the rear defogger switch. Refer to Rear Window Defogger Switch Replacement .

Did you complete the repair?

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System OK

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Test CKT 681 for an open.

Is an open in CKT 681?

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Go to Step 4

Go to Step 5

Repair an open in CKT 681. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

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System OK

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Replace the multi-function alarm module. Refer to Multi-Function Alarm Module Replacement in Keyless Entry.

Did you complete the repair?

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System OK

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