Differential Lock Display Question

[KSMITH1@mailgw.sanders.lockheed.com]

New Question:

On my '88 90Q differential lock switch there is the outline of the 
quattro layout that is illuminated at night.  Centered in the apparent 
location of the rear differential is a bluish-greenish lamp that 
occasionally flickers on without apparent (to me) correlation with 
anything.  What does this lamp signify???  When is it supposed to be 
illuminated/not illuminated??

Thanks in advance

***                 ...Kirby    (Kirby A. Smith)                 ***
***              ksmith1@mailgw.sanders.lockheed.com             ***
***              [=]    kirby.smith@lmco.com                     ***
***  Opinions expressed herein are entirely those of the author. ***