81 Rear defogger

big2bird

big2bird

Charter Member, Founder Bird-Run, Cruise-In Bird-R
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MrsBirswife just reported the rear defogger only stays on 20 seconds or so and goes out. Just tried it, and it appears so. Never have gotten into this thing. I know the elements are fine, and it worked 27 years fine untill now.
Anybody messed with these things? I suppose it's just the internal T/D dying.
 
I thought that these things worked on a heat=resistance circuit, not a timer but I could be wrong. I would check the connections at the switch and at the grids for corrosion first and then go from there.
 
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18436572 said:
That could be a tough one to find.Earlier years had a seperate relay but you should have the all in one.Here is a link if they still have it.(You could just wire in a regular relay and trust the wife to turn it off.)My wife?:rofl:
http://www.parts123.com/parts123/yb.dll?parta~partsort~1
Cant get the link to work.Its at Corvette Central part # 593092 its about $150 ouch
Here is another link. http://app.vendio.com/storefront?view=ITEM_DETAIL&cid=3901072&lid=3048961210&mode=1
Click to expand...

Thank you.
 
Look at your wiring diagram. I think they used a timer/relay since the grid on the window is just a heat element. No sensor of any kind.
 
Mine will stay on as long as I hold the switch in the forward position (yellow light on). But as soon as I release the switch, it goes off.

If it's the switch, and if the switch is $135 + shipping... I'll live with it forever. That switch is probably worth about 10 bucks.:cussing:

.P.S. Once the rear window is de-fogged and the front defroster is on, it will stay clear. I usually have to hold the switch down for approx 1 minute.
 
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Jeff, if you need a switch and can't find one....email me a pix of what you have, I have some old era GM switches for years now, in a bucket somewhere....MAYBE I can help....

:smash:
 
Luster said:
Mine will stay on as long as I hold the switch in the forward position (yellow light on). But as soon as I release the switch, it goes off.

If it's the switch, and if the switch is $135 + shipping... I'll live with it forever. That switch is probably worth about 10 bucks.:cussing:

.P.S. Once the rear window is de-fogged and the front defroster is on, it will stay clear. I usually have to hold the switch down for approx 1 minute.
Click to expand...

I went digging around in some of the camaro parts catalog and found that the early camaro's have the same sw/and set up for the rear window defogger and was able to purchase a new sw for $25 :yahoo:. i will try to find the who i got mine from and post it. I guess the camaro people are not as proud of there switches as the vette vendors are.
 
kwplot34 said:
Luster said:
Mine will stay on as long as I hold the switch in the forward position (yellow light on). But as soon as I release the switch, it goes off.

If it's the switch, and if the switch is $135 + shipping... I'll live with it forever. That switch is probably worth about 10 bucks.:cussing:

.P.S. Once the rear window is de-fogged and the front defroster is on, it will stay clear. I usually have to hold the switch down for approx 1 minute.
Click to expand...

I went digging around in some of the camaro parts catalog and found that the early camaro's have the same sw/and set up for the rear window defogger and was able to purchase a new sw for $25 :yahoo:. i will try to find the who i got mine from and post it. I guess the camaro people are not as proud of there switches as the vette vendors are.
Click to expand...

Let me check the schematic. I believe the siwitch to be good, and the pilot light works. There is a module in the batt compartment.............:huh:
 
big2bird said:
kwplot34 said:
Luster said:
Mine will stay on as long as I hold the switch in the forward position (yellow light on). But as soon as I release the switch, it goes off.

If it's the switch, and if the switch is $135 + shipping... I'll live with it forever. That switch is probably worth about 10 bucks.:cussing:

.P.S. Once the rear window is de-fogged and the front defroster is on, it will stay clear. I usually have to hold the switch down for approx 1 minute.
Click to expand...

I went digging around in some of the camaro parts catalog and found that the early camaro's have the same sw/and set up for the rear window defogger and was able to purchase a new sw for $25 :yahoo:. i will try to find the who i got mine from and post it. I guess the camaro people are not as proud of there switches as the vette vendors are.
Click to expand...

Let me check the schematic. I believe the siwitch to be good, and the pilot light works. There is a module in the batt compartment.............:huh:
Click to expand...

Either way... 25 dollar switch or cheap module in the battery compartment... I'm interested!:bounce:

Keep posting your findings here.

(Of course, I've only used the defogger twice, since I owned it!... haha)
 
I still have a nos defogger switch, it's the one with the green led on it. The 82 had one with an amber lighted lever. What do you have bird? If it's the small one with the LED you can have it for X mas :)

24950f4e5c2e24.jpg
 
Twin_Turbo said:
I still have a nos defogger switch, it's the one with the green led on it. The 82 had one with an amber lighted lever. What do you have bird? If it's the small one with the LED you can have it for X mas :)

24950f4e5c2e24.jpg
Click to expand...

I apprecoate the gesture Marck, but the symptoms point to the module. The switch works, and has the amber lit handle.
 
The amber lit one is larger, the switch and the shifter plate are different. What module is there? I've never seen a module for these things? The module is inside the switch itself.
 
Twin_Turbo said:
The amber lit one is larger, the switch and the shifter plate are different. What module is there? I've never seen a module for these things? The module is inside the switch itself.
Click to expand...

:rofl:Guess I had my "Assume" switch on. Then, I need the switch.
I haven't even looked at it yet, so I never put the two together.:tomato:
 
Good luck finding one, the switches are discontinued and bloody expensive. You can swap to an earlier style shifter plate and use the green led lighted switch. The changeover was somewhere in 81 :) You must have a later car.

There is an amber one on ebay now, used...worn looking.

I had a perfect one that was only missing the black square thing on top that slides over the amber needle, I was about 99.999% sure it worked (worked when removed). Some scumbag on CF wanted it, I sent it to him so he could test if it worked, he never got back to me so he basically stole it. Ffing lowlifes :) Oh, I paid for shipping too LOL
 
It has a black lever stalk, doesn't look original to me. or it must be the pic and the amber looks black
 
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