E28 Taillights

[KiloYankee@xxxxxxx]

Hello all,

This concerns my '84 528e.  I know that the E28 has a inherent problem of the
taillight contacts corroding.  I have replaced the taillight housing gaskets a
year-and-a-half ago, so they're not leaking.  But, the other day, my "brake
light" idiot light came on, and, upon inspection, although both brake lights
were working, the left brake light contacts were all corroded (I'm assuming
this is the aftermath of the leaky taillight gaskets which I replaced 18
months ago).  When I say corroded, I mean the metal contacts where the light
bulb screws into the small cylindrical housing were corroded, as well as the
contacts between the cylindrical housing and the taillight housing assembly.
So, I cleaned all the corrosion off, but the idiot light still came on.  Now,
upon further inspection, the right brake light was in-op.  So, I replaced both
brake light bulbs and everything was fine...for about one hundred
miles...when... the taillight idiot light came on one night...but both
taillights were working!  Then, the brake light idiot light came on shortly
thereafter too, although both brake lights work!  

So, if somebody could tell me how the idiot lights work (as far as what is it
sensing that gives me a light-inop warning) and/or what else I should look out
for.

TIA,

Ed Fens

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