1. Disconnect the rear window defogger relay.
2. Turn the ignition switch to the RUN position.
3. Use a test lamp to probe between B+ and the rear window defogger relay connector terminal A1 (CKT 292).

Does the test lamp light?

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Go to Step 4

Go to Step 2

Use a test lamp to probe between the rear window defogger relay connector terminal C 1 (CKT 293) and ground.

Does the test lamp light?

--

Go to Step 7

Go to Step 3

1. Replace the rear window defogger relay.
2. Test the system again.

Is the repair complete?

--

System OK

Go To Step 2

Inspect for a short to ground in CKT 292 (LT BLU).

Is there a short to ground on the circuit?

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Go to Step 5

Go to Step 6

1. Locate and repair the short to ground in CKT 292 (LT BLU).
2. Retest the circuit.

Is the repair complete?

--

System OK

Go To Step 4

Replace the heater-a/c control. Refer to Control Assembly Replacement in HVAC Systems.

Is the repair complete?

-

System OK

Go To Step 4

1. Locate and repair a short to B+ in CKT 293 (PPL).
2. Inspect the system again.

Is the repair complete?

--

System OK

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