Window Defogger System: Inspection

1. Inspect the defogger switch continuity.
   1. Connect the positive (+) lead from the battery to terminal 2 and negative (-) lead to terminal 3, and then check that the indicator light will light up.
      Fig 1: Testing Defogger Indicator Light

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   If the result is not as specified, replace the switch or bulb.

2. Inspect the defogger timer operation.
   Fig 2: Inspecting Defogger Timer Operation

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   1. Connect the positive (+) lead from the battery to terminal 2 and negative (-) lead to terminal 3.
   2. Connect the positive (+) lead from the battery to terminal 6 through a 1.4 W test bulb.
   3. Push the defogger switch ON, and check that the indicator light in the switch and test bulb will light up for 12 to 18 minutes then the indicator light and test bulb will go out.

If the result is not as specified, replace the switch.

1. Remove the defogger relay from the instrument panel J/B.
2. Inspect the defogger relay continuity.
Fig 3: Identifying Defogger Relay Terminals
Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Standard: 

If the result is not as specified, replace the relay.