Component Tests and General Diagnostics

WINDSHIELD / WINDOW GLASS: WINDOW DEFOGGER WIRE: ON-VEHICLE INSPECTION

1. INSPECT WINDOW DEFOGGER WIRE

NOTICE:
* When cleaning the glass, wipe the glass along the wire using a soft and dry cloth. Take care not to damage the wires.





* Do not use detergents or glass cleaners that have abrasive ingredients.
* When measuring voltage, wrap a piece of tin foil around the tip of the negative tester probe and press the foil against the wire with your finger as shown in the illustration.

Text in Illustration





(a) Turn the ignition switch to ON.

(b) Turn the defogger switch on.

(c) Measure the voltage at the center of each rear window defogger wire to check the wire as shown in the illustration.





Result:





Text in Illustration





HINT
If the voltage is below 1 V, the wire may be faulty between the center of the wire and the wire end on the battery side. If the voltage is 11 to 14 V, the wire may be faulty between the center of the wire and the wire end on the ground side.

(d) Place the voltmeter's positive (+) lead against the defogger wire on the battery side.





(e) Place the voltmeter's negative (-) lead with the foil strip against the wire on the ground side.

(f) Slide the positive (+) lead from the battery side to the ground side.

(g) The point where the voltage drops to below 1 V from 11 to 14 V is the place where the defogger wire is broken.

Text in Illustration





HINT
If the rear window defogger wire is not broken, the voltmeter should indicate 11 to 14 V at the battery side. When the positive (+) lead slides to the ground side, the voltage gradually decreases to below 1 V.