For the record, there is a really weird looking FSU posted today, over here:
> E39 (1997 - 2003) > Fsu replacement
> E39 (1997 - 2003) > Fsu replacement
Here is a pic of the old (on the left) and new FSUs.
You can't see the tag on the new FSU, but it is a Behr/Hella Service model that was made in China. I gently chiseled up the epoxy from it (per kraft's great thread here): www.bimmerfest.com/forums/showthread.php?t=309399"]http://www.bimmerfest.com/forums/showthread.php?t=309399 and came up with this:
If you've looked at the pictures other people have posted, this doesn't look anything like those. This FSU has a fairly thick layer of epoxy underneath which is the circuit board. Surprisingly, the circuit board is surrounded by a layer of silicone. The circuit board itself is much smaller than the pictures of other circuit boards I've seen. I would bet that this is the reason this piece of crap failed... cheap Chinese circuit boards.
I tested the resistance between the posts and body per this:
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...and my resistance values were different from those listed on the picture. Some were at the new value and some were at the old. I also tested resistance on the old FSU and the readings were fairly similar, some in the new range and some in the old.
It looks like I'm going to have to pay the piper with this purchase, but hey, it was only $50 for the Chinese one from autohaus, the same part from the dealer shouldn't be more than twice that, right? I called the only two local BMW dealerships in the Portland area and they both want $164!This car is such a pain in the @$$ sometimes...
If buying and installing the factory BMW FSU doesn't fix this stupid battery drain issue, I'm going to seriously consider selling this car.
Ok, now that I'm back from the Portland BMW dealership (with a $164.35 lighter wallet), I've got some information to share with all of you that should hopefully clear up confusion in the future.
This is a pic of all three FSUs; the original on the left, the cheapo Chinese knockoff in the middle, and the BMW OEM dealership (German-manufactured) FSU on the right:
This is a slightly closer picture of the Chinese FSU next to the OEM FSU. Yeah, I know the Chinese heat sink is all F-ed up, I was attempting to remove the outer plastic casing with a hammer and got a little carried away...
Here's where it gets interesting:
This is a closeup of the Chinese FSU. As you can see, there's no visible markings other than the manufacturing ridges.
Here's a closeup of the same area on the German version:
There is some small print visible. Now, obviously this is not conclusive evidence, but it may be a tell-tale sign of a quality, German-made part and a cheap piece of doo-doo like I originally bought.
It's hard to tell through pictures, but the difference in quality between the German and Chinese versions are blindingly obvious in person. If you look closely, you can see the difference in the casting quality of the heat sinks. Talking to the guy at the parts counter at the dealership, he told me he had replaced one of these over five years ago on his Bimmer and had zero problems since. Plus, if I do have a problem in the future, I've got a two-year warranty. Not something I had with the Chinese version.
I'll keep you guys posted with another update in a couple of months... and hopefully it's a good one.
