Author Topic: Rear Window Defogger Ground.  (Read 6174 times)

BlackoutSteve

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Rear Window Defogger Ground.
« on: June 15, 2009, 11:46:14 AM »
I posted this over at Camaros.net, but unfortunately haven't received any responses.
Hopefully someone here can help me.
JohnZ, I understand you have an OE unit. A search brought up text, but none of the pictures you posted.


I have this rear window defogger for my 69..
This is how I received it when I bought it maybe 15 years ago.
It shows the ground strap fastened under one of the vent mounting screws.



Does anyone know if this is this correct? Reason I ask is because with the painted surfaces of the defogger housing and parcel shelf, the ground is very poor if any electrical connection at all to the body.

Unfortunately the AIM C50 chapter only shows the switch installation, and the Fisher Body Manual shows nothing. (I'm hoping I overlooked it somewhere.)

Going by clues of the type of serrated keps-nut (nut with integral star washer) that fastens the ground wire, which also has a serrated eyelet, I expect that these are incompatible with each other and the defogger should be positively grounded elsewhere. (or is that negatively grounded elswhere? ) I don't see the point of grounding to the housing of the defogger when it's not making a contact to the body.
Restoring my RHD 69 Jane in Melbourne, Australia.
http://www.usmuscle.com.au/Forum/showthread.php?t=2840

mark x22

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Re: Rear Window Defogger Ground.
« Reply #1 on: June 15, 2009, 09:17:42 PM »
mine works okay . have you put in your switch yet ?

BlackoutSteve

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Re: Rear Window Defogger Ground.
« Reply #2 on: June 16, 2009, 09:48:15 AM »
No, not yet.. I am assembling the car after a rostisserie resto, so a little while before I switch it on.
I just gave the defogger a new coat of paint and was concerned about it grounding. I thought maybe the fround was supposed to be via a screw to the body.. like the fuel tank's sender for example.
Thanks Mark.
Restoring my RHD 69 Jane in Melbourne, Australia.
http://www.usmuscle.com.au/Forum/showthread.php?t=2840

mark x22

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Re: Rear Window Defogger Ground.
« Reply #3 on: June 16, 2009, 10:38:09 AM »


  you can print these full size

JohnZ

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Re: Rear Window Defogger Ground.
« Reply #4 on: June 16, 2009, 02:18:24 PM »
Mine's an untouched original, and the black ground wire is under the right front blower housing attachment stud with a Keps nut.
'69 Z/28
Fathom Green
CRG

BlackoutSteve

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Re: Rear Window Defogger Ground.
« Reply #5 on: June 17, 2009, 11:40:54 AM »
Thanks Mark. :-* Thanks John.  :-*
Restoring my RHD 69 Jane in Melbourne, Australia.
http://www.usmuscle.com.au/Forum/showthread.php?t=2840

My68SS

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Re: Rear Window Defogger Ground.
« Reply #6 on: June 22, 2009, 07:33:19 PM »
Hey Steve, how's Melb! Good to see your still at it. Mines still a 'slide rule snapping' 'work in progress'  :(  But I've gathered lots of little bits here and there.
I occasionally look at the pics you sent me for inspiration! :)
Rob
1968 12C SS
L34/M40
12 bolt posi 3.55

BlackoutSteve

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Re: Rear Window Defogger Ground.
« Reply #7 on: June 25, 2009, 10:47:20 AM »
Hey Rob!  :D
Restoring my RHD 69 Jane in Melbourne, Australia.
http://www.usmuscle.com.au/Forum/showthread.php?t=2840