Heated Glass Element: Testing and Inspection

CAUTION:
Wrap tin fail around the end of the voltmeter test lead to prevent damaging the heater line. Apply finger pressure on the tin foil, moving the tin toil along the grid line to check for open circuits.







1. Turn on the defogger switch and use a voltmeter to measure the voltage of each heater line at the glass center point. It a voltage of approximately 6V is indicated by the voltmeter, the heater line of the rear window is considered satisfactory.




2. If a heater line is burned out between the center point and (+) terminal, the voltmeter will indicate 12 V.




3. It a heater line is burned out between the center point and (-) terminal the voltmeter will indicate 0 V.




4. To check for open circuits, slowly move the test lead in the direction that the open circuit seems to exist. Try to find a point where a voltage is generated or changes to 0 V. The point where the voltage has changed is the open-circuit point.




5. Use an ohmmeter to measure the resistance of each heater line between a terminal and the center eta grid tine, and between the same terminal and the center of ore adjacent heater line. With a broken heater line will have a resistance twice as that in other sections. In the affected, move the test lead to a position where the resistance sharply changes.