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jamis1970 · Joined: 08 Oct 2010 Posts: 56 Location: big bear lake 92315

Hello, One of the two defroster tabs have come off. I have a question about the wires. on my car I have a hot power black wire driver side that looks to connect to the strut. (struts were replaced by PO and these do not have a tab for power lead.) And this supplies power to grid. My question is does the hot lead connect to both tabs? I have one on drivers side and one on pass side. Based on my research I thought it worked like this. Power comes to driver side connects to tab on strut drivers side, and the ground is pass side strut. How should i wire this? Power drivers side to driver side tab, then ground wire from pass side tab to body? or hot lead to both tabs driv and pass and then the pass side strut grounds?
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1979 924 N/A Not Fast, but a BLAST to drive.

924RACR · Posted: Sun Oct 02, 2011 10:00 pm Post subject:

You have it correct; the power is passed through the strut body itself on the LH side, and grounds through the strut on the RH side. For this scheme to work requires use of the correct struts; the LH strut MUST be isolated from grounding on the body with plastic ends, whereas the RH strut usually has a metal cup end at the body. Otherwise you might blow a fuse.

That said, I've often found the ground to be pretty weak, and have run a separate ground lead on the RH side directly down the strut to the ground lead. I used 2 10-ga wires, as there's a LOT of current flowing there...
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Vaughan Scott
Webmeister
'79 924 #77 SCCA H Prod racecar
'82 931 Plat. Silver
#25 Hidari Firefly P2 sports prototype

Smoothie · Posted: Mon Oct 03, 2011 1:58 am Post subject:

+1^
+> Check the 12v+ wire on the left for fraying. If it's frayed and hanging on by just a few strands like mine was, it'll still read 12+V, but won't carry enough amps/watts to sufficiently heat the defroster.

The OEM/factory right side grounding strut was designed to open the ground (switch off power) when the hatch is opened. Can't imagine why this feature would be absolutely necessary, so I have to agree - run an extra wire on the ground side...
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"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox