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window winder relay TOO HOT to TOUCH!!!

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Old 07-07-2002, 01:18 PM
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keith
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Post window winder relay TOO HOT to TOUCH!!!

This can't be normal...?

This is while sitting, with key on, as I was troubleshooting my sunroof.

I guess I'm shopping for a relay, huh?

You guys who know, let me know, please!

BTW, my sunroof, which hasn't worked since I owned the car (about 4 years) had a single bad relay on the motor. <img src="graemlins/r.gif" border="0" alt="[king]" />
Old 07-07-2002, 03:00 PM
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Dave951M
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Keith-

Have you checked into the condition of the motor and winding mechanism? Mine went slowly and would heat up, then I opened it up and found it full of 16 year old crud, cleaned it out, regreased, and reset the friction clutch and it works smoothlly now.

How's the 931 coming?

Dave
Old 04-25-2004, 05:51 PM
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Rally Guy
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Bump - I'm getting the same symptom - is it the relay or the winder motors?

Thanks,

RK
Old 04-25-2004, 10:31 PM
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Zero10
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LOL!!! FINALLY SOMEBODY ELSE WITH THIS PROBLEM!!!

Okie dokie, my relay got so hot it melted the case on a couple of them, so I am now running a relay without a case on it.

It will get hot without even operating the windows, right?

I tried replacing my relay, twice (they were used, so I guessed maybe the one I got was bad), no luck. I checked out all the wiring I could follow/find, no luck, checked out all 3 switches, all good. I never checked the motors though, found it was too difficult. Just lived with it, hoping my car doesn't burn to the ground.

Be sure to let us know what you learn about this problem.
Old 04-25-2004, 10:33 PM
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Cyrus951
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I got the same problem, that POS burns like crazy..
Old 04-25-2004, 11:17 PM
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Rally Guy
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Okay - this seems common - and yet no one seems to have solved it. (this is SOOO an Iceshark issue - I'm sure he'll chime in!)

I'll start the "thought experiment" right now and someone who's actually smart can chime in and maybe set us straight...

First - why a relay? It allows a heavier current to be switched remotely - negating the need for the "working" current going all the way to the switch.

Okay - if that's the case - are the window switches controlling the relay - which is in turn operating the motors? Seems a bit strange to run the current all the way FROM the door to the relay then back to the door.

Perhaps the wiring diagrams will tell us.

In any case - heat in any component suggests LOTS of current or LOTS of resistance - correct?

So either, a) the relay is managing lots of excess current ( then the q becomes why) or b) the relay is introducing LOTS of resistance (suggesting a bad relay).

Okay - I'm well past my understanding of this stuff - who can set us straight and hazard a guess at why the relay is getting so hot?!?

Thanks in advance!
Old 04-26-2004, 03:30 AM
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Zero10
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Okay, here's what I know.
I drew out a wiring diagram of the relay, and then I lost it =(
So, that was pointless to say, but here's what I learned from taking my relay apart.
It's the resistor at the top that heats up, it is in series with the coil for the contacts on the relay.
It is also connected to another terminal on the relay, which I thought was really, odd, but I don't know which one off hand, and I don't know what that terminal is connected to.

Yes it's a little unusual to use an additional relay, and yep, it means that current flows all the way up to the relay and back, I believe the contact allows the +12V to reach the window switches.

I thought it was really strange that they would use a 1 watt 56 ohm resistor in series with the coil. Look at the size of the wire in that thing, I am fairly certain that a 1 watt resistor is overkill, yet it still overheats. It must be for something else as well. When I work it out, if you were to apply 14V to the resistor, it would dissipate 3.5W, which would cause it to severely overheat, so it sounds to me like the other terminal that it is connected to is being grounded, which would explain our symptoms? Or perhaps the other terminal is having power applied, I can't recall the direction of current flow through the relay. While my fiberglass is drying tomorrow, I will grab my meter, and check this out for us.

I will pull my relay tomorrow, and try to re-sketch the circuit diagram of it.

I hope we can fix this bugger, my relay gets so hot it cooks the turn signal relay, and my turn signals keep sticking on (not the arm, but the lights don't blink), unless I flick the relay, or blow on it to cool it back down.



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