Component Tests and General Diagnostics

DEFOGGER SWITCH INSPECTION
(into Air conditioning control panel)

1. INSPECT SWITCH OPERATION





(a) Connect the positive (+) lead from the battery to terminal A6 and negative (-) lead to terminal A7.
(b) Connect the positive (+) lead from the battery to terminal B10 through a 1.4 W test bulb.





(c) Turn the defogger switch ON and check that the test bulb and indicator light turn ON. then turn OFF after about 15 minutes.
If operation is not as specified, replace the air conditioning control panel assembly.

DEFOGGER RELAY INSPECTION

1. INSPECT RELAY CONTINUITY
If continuity is not as specified, replace the relay.

2. INSPECT RELAY CIRCUIT

DEFOGGER WIRES INSPECTION











1. INSPECT DEFOGGER WIRES
DEFOGGER WIRES INSPECTION











1. INSPECT DEFOGGER WIRES

NOTE:
^ When cleaning the glass, use a soft. dry cloth and wipe the glass in the direction of the wire. Take care not to damage wires.
^ Do not use detergents or glass cleaners with abrasive ingredients.
^ When measuring voltage, wind a piece of tin foil around the top of the negative probe and press the foil against the wire with your fingers, as shown.

(a) Turn the ignition switch ON.
(b) Turn the defogger switch ON.
(c) Inspect the voltage at the center of each heat wire, as shown.

HINT: If there is approximately 10 volts, the wire is broken between the center of the wire and the positive (+) end. If there is no voltage, the wire is broken between the center of the wire and ground.





(d) Place the voltmeter positive (+) lead against the defogger positive (+) terminal.
(e) Place the voltmeter negative (-) lead with the foil strip against the heat wire at the positive (+) terminal end and slide it toward the negative (-) terminal end.
(f) The point where the voltmeter deflects from zero to several volts is the place where the heat wire is broken.
HINT: If the heat wire is not broken, the voltmeter indicates 0 volts at the positive (+) end of the heat wire but gradually increases to about 12 volts as the meter probe is moved to the other end.








2. REPAIR DEFOGGER WIRES
(a) Clean the broken wire tips with a grease, wax and silicone remover.
(b) Place the masking tap along both sides of the wire to be repaired.
(c) Thoroughly mix the repair agent (Dupont paste No. 4817).
(d) Using a fine tip brush, apply a small amount to the wire.
(e) After a few minutes, remove the masking tape.
(f) Allow the repair to stand at least 24 hours.