[V6-12v] Rear Defogger Switch - 90 v. A6

[Eric Ragot]

two cars of mine - 94 90s & 96 A6.
the light on the 96 defogger switch does not come on when it is depressed.
the 94 switch works.
I pulled them out and compared - each switch has 6 pin outs. The A6 uses 
all 6 while the 90's switch leaves pin #4 empty. Both switches seem to work 
in either car (I didn't get all hot and heavy in the A6, so I really don't 
know if it worked actually).

Does anyone know what the heck pin #4 is used for on the A6 and if I risk 
anything by using a switch that doesn't have that connector?

Thanks,
Eric