Turn on the rear window defroster.
Fig. 7.90. Checking the rear window heating thread
Caution! Touching the rear window heating filament with the tester probe may damage the filament. Wrap aluminum foil around the end of the probe and check the filament by touching it with the foil (Fig. 7.90);
Fig. 7.91. Connecting the tester probe to the ends of the thread
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Connect the positive probe of the tester to the positive end of each wire and the negative probe to the body ground (Fig. 7.91).
By moving the positive probe from the positive end of the thread to the negative end, make sure that the voltage decreases accordingly.
If the voltage changes quickly, the filament is faulty. Repair the filament.
