Question on rear window heating elemnt wiring

[tdskip]

Hi guys - hope everyone had a good weekend.


I found loose wires under my parcel shelf wiring, I am assuming from my DPO since they were kind of just jammed under there.

I found several brown (ground) wire tucked away back there as well as two other non-ground wires. One is red with a black band, and the other is red with white rings on it. Could someone confirm that I'm reading the wiring diagram correctly?

Is the red / black band is from the rear fuse box to the rear window heating switch?

Is the red / white ring from the rear window heating circuit?

Thanks!

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Pictures of wires as found;

[ossiblue]

This is from memory so it may not be 100%.

you have a two stage window defogger element. The red/black wire comes from the defogger relay in the engine compartment and connects to the lower prong on the left side of the widow. The red/white wire also comes from the relay and connects to the upper prong on the left side of the window. The brown ground wires pass to the right side of the window, under the installed seal, and connect to the upper and lower prongs on the right side.

Again, this is from memory and hopefully someone can confirm or correct this for a 74.

[E Sully]

The wiring diagrams show a single stage heating element. On a 2 stage relay there would be a contact labeled 86a where the white/black is connected, and a red/black to the additional heating element in the window.
With the 2 stage, the first stage is activated by the black wire from the defrost switch to the relay, and the red/white from the relay to the element. The 2nd stage is activated by the white/black from the switch to the relay, and the red/black from the relay to the heating element. Brown wires being grounds.

[86 911 Targa]

From my friend @ Hella:

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Thanks guys - very helpful.

So here is a basic question - where are these supposed to physically connect on the car?

[schumicat]

there are male connectors for the defrost wires in the side of the rear glass hidden in the rubber seal. you may be able to see them if you look closely and gently pull the seal back from the inside. the seal has channels used to run the wires up to the connectors and you poke holes to run them to the connector. it is a pain to run the wires and easier to install the seal without running them (especially if you live in a warm area and don't use defroster), so that may be why they were left loose when the seal or window was replaced at some time in the past.

[tdskip]

There you go - thanks.

L.J. - sorry it didn't click when you explained it the first time. Long day already at that point.