My rear window was rattling so I decided to add the Rear Window Defroster option since I needed to remove the glass to replace the seal. I bought the switch, wiring harness, and window in excellent shape from a guy who removed them from his car. He even gave me a hand drawn schematic diagram.

I did continuity tests on three parts and they are good. I found all of the connection points and laid out the harness. It looks like it starts at the switch, goes under the dash to the fuse panel, runs back along the left side of the interior floor, then along the bottom of the firewall. I haven't taken the back pad off, but it is unclear where it should route from the passenger compartment through the firewall and to the relay board.

My car is a 1975 1.8 model if that matters.

I need the factory routing of the wiring harness.


Can anyone help?

Thanks,

Bob

[quote name='Mowog4' date='Jan 18 2017, 07:21 AM' post='2445128']
[quote name='AZAircooled' post='2444864' date='Jan 17 2017, 01:33 PM']
My rear window was rattling so I decided to add the Rear Window Defroster option since I needed to remove the glass to replace the seal. I bought the switch, wiring harness, and window in excellent shape from a guy who removed them from his car. He even gave me a hand drawn schematic diagram.

I did continuity tests on three parts and they are good. I found all of the connection points and laid out the harness. It looks like it starts at the switch, goes under the dash to the fuse panel, runs back along the left side of the interior floor, then along the bottom of the firewall. I haven't taken the back pad off, but it is unclear where it should route from the passenger compartment through the firewall and to the relay board.

My car is a 1975 1.8 model if that matters.

I need the factory routing of the wiring harness.


Can anyone help?

Thanks,

Bob
[/quote]
Bob
Did you figure this out? I have a similar question and will be wiring it this weekend.

The harness follows the main wiring harness route from the dash switch down the firewall through the tunnel. The window wires come up out of the tunnel behind the back pad both left and right to the window. The relay panel plug has to go though the rubber gooseneck and up to the relay panel. The trick is to remove the plastic connector ( good luck getting it apart without breaking it) and reinstalling it before you plug it in. the lead from the switch to the front fuse panel goes to a switched fuse as I remember. This power source is only for the switch light, the actual defroster is powered from the relay panel.

Thanks John.