Component Tests and General Diagnostics

INSPECTION




1. INSPECT DEFOGGER TIMER OPERATION
a. Connect the positive (+) lead from the battery to terminal 1 and negative (-) lead to terminal 3.
b. Connect the positive (+) lead from the battery to terminal 5 through a 3.4 W test bulb.
c. Turn the defogger switch ON and check that the indicator light and test bulb light up for 12 to 18 minutes, then the indicator light and test bulb lights go out.
If operation is not as specified, replace the switch.







2. Connector disconnected:
INSPECT DEFOGGER SWITCH CIRCUIT
Disconnect the connector from the switch and inspect the connector on wire harness side, as shown in the chart.
If the circuit is not as specified, replace the switch.




3. Connector connected:
INSPECT DEFOGGER SWITCH CIRCUIT
Connect the connector from the switch and inspect the wire harness side connector from the back side, as shown in the chart.
If the circuit is not as specified, try replacing the switch with a new one.
If the circuit is not as specified, inspect the circuit connected to other parts.







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

5. INSPECT DEFOGGER WIRE






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 the 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 finger, 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 V, 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 V is the place where the heat wire is broken.

HINT: If the heat wire is not broken, the voltmeter indicates 0 V at the positive (+) end of the heat wire but gradually increases to about 12 V as the meter probe is moved to the other end.