Thu, 05 Aug 1999 08:41:27 +0300 - Message No. 6179
From: "Ari Peltola"

Subject: Melted plastic parts (douple-low experiment completed)


SH*****T,  I opened the switch and it was bloody
melted....things were just like Marc descriped
(his mail below). After Marc many others have 
told exactly the same.

Instead of douple-low-douple-high AT I only got
mono-low AT now (after about 5000 km). 

Got to see my switch dealer soon...

Ari
Finland
#281

>>> Marc Luethi  4.8.1999 (Wed) 16:22 >>>
At 10:44 04.08.1999 +0300, Ari wrote:
>OHH NOOOO, is this a punishment of self-made-douple-
>low-beam-connection I made last autumn? 
>I dont believe it yet....someone disagree??

Yes it is, I am afraid!

Let me explain in an ASCII drawing:


schematic side view of the switch:

           <---         --->
 
      ---------------------------             BBBBBB
      |   I       >>         I   |-----------|BBBBBB
      |   I       <<         I               |BBBBBB
      |   I       >>         I   |-----------|BBBBBB
      |---I_______<<________ I---|            BBBBBB
 ____CCCCCCCCC______CCCCCCCCCCCCCCCCC_
|_____________________________________|
        /                /
       /                /
      /                /


ok... the B is the red High-Beam-Switch-Button.

The   I        I  is a U-shaped metal part, approx 5x3mm in size
      I________I

The >> is a little spring that presses the U-Shaped part agains the
Cs, which are "contact rails" on a small "Chip", represented by 
 ____________
|____________|


The / are the cables connecting to the contacts from the other side.


The  ------		 is the "sliding" part of the switch which is moved 	
    |      |-------
    |              |
    |      |-------
     ------
in and out when you press the switch.


What has most probably happened is this:

Due to the double amount of current flowing through the U-shaped metal
thingy, 
it has become considerably hotter than before. This has caused the "slider" 
not to be burnt but to melt a little. Now this will not allow that
U-shaped-metal 
thingy to slide up and down properly anymore. It has gotten more freeplay
than before, 
has misaligned itself and got stuck in the slider whithout touching any of the
Contacts on the base plate anymore.

Solutuion: *VERY, VERY* cautiously take the switch apart, TAKE CARE not to
damage 
the "lock" mecanism which holds your slider in place once it's pressed.
Then free the U-shaped thingy from its stuck position and check that it now
can slide
up and down again against the little force of that tiny spring that is
meant to 
hold it in place.

Well.. I had to repair this thing twice, on both twins. The first switch
survived and is
still working, the second switch now has a damaged "lock mechanism". So be
careful.

Greets

Marc


-- 
marc@rrr.de                                           YJ@IRC 
http://www.rrr.de/~marc/                   






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