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Wiring Woes

Discussion in 'E30 (1984-1993)' started by altazansw, May 21, 2009.

    altazansw guest

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    Greetings All. I just purchased my first BMW, 1987 325i with a 5 speed. The dealer said its battery was bad and wouldn't hold a charge. Figured it was no big deal, jumped it off and I drove it home (I test drove it a couple of weeks ago).
    When I got home and put it in the garage where it was dark, I realized that the Instrument Panel, rear marker, and license plate lights were on. Got the wiring diagram, chased it down to the headlight switch, and realized the wiring to it was melted. Mainly the Gray/Red wire. Several others were melted from the 25 pin connector towards the instrument panel, and from the connector towards the firewall. It looks like one of the previous owners botched a splice and the electrical tape came off.

    Should I try to rewrap all the wires?
    Can I get a new harness from the connector to the instrument panel?
    Where's some good places to buy parts?

    Thanks!
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    granthr

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    If the damage is just located at the headlight switch it should be a pretty easy fix. Either go to a local junk yard and hope they have a few e30s to cut out the needed section of the wiring harness or call some of the BMW dismantlers in the back of Roundel. Just tell them you want a headlight switch with about 4 inches of the wiring harness with it. That should give you plenty of wire to work with to do a proper repair job.

    You may know this, but use solder and those heat shrink tubes to do a top notch job.

    Also be sure to get a switch that matches your car. I think on the e30s they changed the wiring connectors around 90/91. My 88 has the older style and my 91 has the newer style. The change might of happened when they added an airbag, but I can't say for sure.
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    CRKrieger

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    Good suggestion but for one thing. Why cut when you can unplug? The yard isn't going to charge much for something they hardly ever sell, so I'd take as much of the harness as will allow me to simply unplug and reconnect ... and avoid soldering altogether.

    altazansw guest

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    Our local U-pull it yard has an 89 3 series. Will the harnesses I need work? Were there many changes from 87 to 89? They only want 11 bucks for the harness!
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    granthr

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    I agree completely. But, I am just not sure if the wiring loom going to the headlight switch is hard wired into the main wiring harness. If it is, then really the only option is to cut and solder. Unless he wants to replace the whole harness, which is a big job.
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    granthr

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    I would say go buy it or at least go and look at it to see if the connectors match. You will know right away. Look at the connector that goes to your headlight switch and compare it to what they have. They are different enough that you can tell just by looking at them. I would suggest getting a new switch too, sounds like your old one has a short in it. If you can't source a used one locally, call the used parts advertisers in Roundel. You will find one in less then 5 calls/15 minutes.

    altazansw guest

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    Update

    Went to the Pull-A-Part yesterday, The harness had the wrong connectors. I went ahead and pulled the whole thing out (its easy when the seats, dash, carpet, etc. are out). I'll have to sit down with the wiring diagrams and graft the circuits/connectors that are melted. As damaged as the headlight portion of mine is, I'll use the different connector from the '89, and replace it with an '89 headlight switch. I also got a battery cover. Not bad for 14 bucks!
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    granthr

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    You have to love junk yards and their names! There are two in my area called "You Pull It" and "U Pull It". As you know, you can usually get good deals. Especially if you come across a car with desirable parts on it, like "IS" spoilers, sport seats, etc.

    Hope the wiring goes well.

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