rear window heater grid.........

[Toploader]

So now that I can control the heater grid with a generic round rocker switch I find that only the bottom half of the window gets warm, top remains cold.
Any suggestions as to where I should now look to obtain 100% efficiency???

[friskyfrankie]

Do voltage checks on the lowest grid that works and work your way up. Somewhere there is a break in the grid.

[Toploader]

Do voltage checks on the lowest grid that works and work your way up. Somewhere there is a break in the grid.

Thanks Frank, I realize that even a tiny break in the wire results in no voltage in the rest of the grid. I will have to go over the window with a fine tooth comb. Its nice having a rear defog that "works".

[friskyfrankie]

Thanks Frank, I realize that even a tiny break in the wire results in no voltage in the rest of the grid. I will have to go over the window with a fine tooth comb. Its nice having a rear defog that "works".

Yes it is but they can be quite finicky!

[Toploader]

Do voltage checks on the lowest grid that works and work your way up. Somewhere there is a break in the grid.

For this "dummy" volt meter in hand...................where do I place the leads? Also I assume the meter is on DC volts.

[friskyfrankie]

This should explain it along with other Youtube videos you can always find.

https://www.youtube.com/watch?v=tny-8wGGcw4&t=50s

[Toploader]

This should explain it along with other Youtube videos you can always find.

https://www.youtube.com/watch?v=tny-8wGGcw4&t=50s

Sadly the grid layout on my '86 is nothing like this;-(

[friskyfrankie]

Sadly the grid layout on my '86 is nothing like this;-(

The overall process should, however, be the same. The voltage will change as you move from the extreme sides of the grids to the middle so be aware of that. I am sure there are some Ford videos that will be closer for your comfort level. .

[Toploader]

Thank you!