I need to re-wire my rear defroster.

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mkory
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I bought my car with a Clifford alarm and remote starter. When I use the remote start, the heat starts working as usual, to whatever setting it was set on before I turned it off. The only problem is that the rear window defroster doesn't come on, because it resets every time the car gets turned off. Is there any way I can screw with some wires there to make it reset and automatically be on. Having a remote starter just doesn't have the same effect when you have to go out there anyways so you can turn on your rear defroster.


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mkory
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bump

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mkory
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Oh God, I really hate it when people bump their own posts, I think its stupid, but I know somebody knows how to fix this and I really do need an answer.

pmkls2
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you could probably hot wire it but honestly its best to leave it alone, rear defrosters put a tremendous load on the electrical system and they are designed to shut off after a certain time or when the resistance drops and I think that hardwiring one would cause it to run all the time and it would eventually melt down one of the components in the system

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mkory
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Hmm... Good point, but can't I just default it to on, or since my driving lights come on about 10 seconds after the car starts, could I wire it up to them somehow. I'm thinking, somehow wire the rear defrost to come on with the driving lights, then put it on a switch to turn it off. That way I could flip the switch on at night when my car's off, and the defrost would automatically come on with the driving lights when I use te remote start the next morning. Then just flip it again when I get in the car to turn it off.

pmkls2
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Well, I need to do some thinking on that one lol...........

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mkory
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I don't see any reason why it wouldn't work. How big of a drain does the defrost cause anyways? It just seems as simple as cutting and twisting wires, and throwing a switch in there.

pmkls2
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my point is it is not as simple as twisting some wires together. the draw depends on the temperature actually, as the temp raises the draw increases and that is what turns off the defogger automatically so it needs to be wired to be able to turn off after it has served its purpose , you have to be able to wire it in such a manner that it will come on when you hit the start button but still turn off automatically, which needs to be thought out pretty thoroughly because if the defogger runs too long it will melt down something in the system like some wires or a relay because they are only designed to be run for certain lengths of time due to the high current draw they create especially as the temp increases on the grid of the glass

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mkory
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How about this, when I get in my car and do turn the key, I can hear something under the dash click, then the car acts like it normally does when it runs. (radio, wipers, other things that only work when the key is on). Most systems work when the remote start is used, but not all of them not just the remote start. Also, when I put the key in, the parking lights turn off. So, how about wireing it so it will automatically turn on with the remote start, like the parking lights, but turn off when the key is inserted. Then, after I put in the key, just manually push the button to turn it on. (since I'm in the car anyways) How's this set up sound?

pmkls2
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that may very well work, give it a try and let us know how it goes

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mkory
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I would try it, but I have no ideas what to do with which tires. Anyone know how about this should work off the top of your head?

pmkls2
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well, you need to get a wiring diagram for the defogger and get a diagram for the remote starter, you would be kinda working in the dark without them..............

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mkory
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How do I go about getting one of those?

pmkls2
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well you will need a FSM to get the schematic for the defogger and as for the remote start find out the brand and try going to their website and seeing if they can give you an installation manual which will have a hook-up schematic for you

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Dragon240
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Not to hijack but I have a defroster problem as well.. Mine only works in the bottom middle area about 3-4 lines up and not from one side to the other.. It's all hooked up but its not working.. What can be done to test those things? Repair?

pmkls2
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if some lines are operational and some are not then the lines that are not functioning are broken which happens very easily. it isnt that difficult to test a defogger grid, you just take a test light and place the ground lead on one side of the line and the probe on the other side and slowly work your way across the line until the light goes out. once the test light goes out then you have pinpointed the break in the grid. the only fixes I have seen are kinda messy and difficult to apply but they do work and are much cheaper than replacing the while back glass, there are defroster grid repair kits available, but you will just have to search to find where to buy them because I have only dealt with GM ones but Im sure plenty other companies make hem as well


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