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Jeff
01-21-1999, 11:51 AM
Could someone please repost the instructions on how to repair the lamp control unit? My understanding is that it involves soldering a circuit board....<p>Thanks! <p>Jeff<br>90 535i

Shawn Anderson
01-21-1999, 12:58 PM
These is what I did to resolder the LCM when my low beams started acting with a mind of their own (Low beams would turn off for no reason. This made night driving very exciting).<p>It is pretty easy. Took maybe 15 minutes. I actually had to do this twice because the first time I missed a bad solder joint.<p>1. Remove the Lamp Control Module (LCM). It is in the fuse box and is aproximately 1 inch by 6 inches or so. I think is has LKM printed on it.<p>2. Remove the cover from the LCM. You'll need to get a couple of knives or small screwdrivers to lift the notches that hold the cover onto the base. Slowly slide off the cover.<p>3. Now you should see the LCM board. You will notice 3 or 4 small relays that are soldered onto the board. This is usually where the problems occur. I think they tend to vibrate and crack the solder. Look VERY closely at the connections at the back of these relays. You will probably see very small cracks in the solder.<p>4. I would recommend reheating all the solder joints for the relays on the board. Don't bother with everything else, just the relays. Like I said, I missed a couple the first time bacause I only did the one pin that was obvious. <p>5. Put is back together. <p>Shawn Anderson<br>1990 535<p><p><i>: Could someone please repost the instructions on how to repair the lamp control unit? My understanding is that it involves soldering a circuit board....<p>: Thanks! <p>: Jeff<br>: 90 535i<p></i>

ron
01-21-1999, 03:13 PM
<i>: Could someone please repost the instructions on how to repair the lamp control unit? My understanding is that it involves soldering a circuit board....<p>: Jeff, here's what i posted a few weeks ago when someone else was having same problem....same fix Shawn described, but i also put some foam chunks on the edges of the card to keep it from moving around. It's pretty easy...good luck!<br>ron 89 525i<p></i>--it was the LCM on my 89 525i that caused my driver side low beam to visit me when it wanted to. BTW, all your lights are controlled by this little Hella circuit card. I had the car going in for an inspection anyway, so i asked them to look at the lo beam problem too. They resoldered the legs of all the relays (charged me $50 labor) and it worked great for about 2 weeks, then same thing again. This time i checked it out myself...it looked like Ray Charles did the soldering. I removed the globs and re-soldered it. I also put a small wedge of foam rubber on the edge of the circuit card since i believe it's the constant vibration of this card in its little plastic box that causes the solder to crack. Anyway, it's been almost 2 years without an LCM problem. And no, i didn't get my $50 back....yet.

Steve
01-21-1999, 04:24 PM
Stating the obvious but.. in case your not used to electrical soldering - add a little fresh solder (flux cored) to wet the existing solder and make a good joint.<p><i>: These is what I did <snip><br>: 4. I would recommend reheating all the solder joints for the relays on the board. ,snip><br>: Shawn Anderson<br>: 1990 535<br>

Jeff
01-21-1999, 06:33 PM
Thanks everyone!!<p><i>: Could someone please repost the instructions on how to repair the lamp control unit? My understanding is that it involves soldering a circuit board....<p>: Thanks! <p>: Jeff<br>: 90 535i<p></i>


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