How to Service a Rear Window Defogger in a Nissan Pathfinder

Introduced in 1966 by Volvo, the rear window defogger lets you see out through the rear view mirror in cold weather and melts snow and ice from the rear window. The device is now available for most cars, minivans and SUVs. Identify any problems and service the defogger in less than 30 minutes.

Instructions

Check the Electric Fuse and Wires for Power

1

Remove the defogger fuse in the fuse box. If the fuse is broken (hold up to the light to check), replace.

2

Check the relay with an ohmmeter to make sure current runs through it. To find the relay in the Pathfinder, check the owner's manual. In many models, the relay is near the left rear interior quarter panel, behind the opening in the panel.

3

Use the ohmmeter to check the external wire connecting the back of the vehicle to the window. This wire can sometimes get kinked or broken in the process of loading or unloading cargo. It can be replaced or soldered.

Find Breaks in the Defogger Tab and Grid Filament

4

Make repairs to the grid element or filament at temperatures above 50 degrees F. In cooler weather, allow the repair to cure for 24 hours before testing the system.

5

Examine the grid filament on the back window, as any breaks can cause the entire system to fail. From the inside of the car, start from the defroster tab and examine the filament for breaks. To repair, get the kit from Frost Fighter or Permatex. Mask the broken section with masking tape and paint with silver conductive paint.

6

Test the defroster tab on the rear window. These fragile components are easily knocked off and can be reattached with an adhesive that conducts electricity. You can purchase kits containing just the tabs and conductive glue.