This is kind of a funny coincidence:  I mean here in Southern California with garage kept Vanagon, I NEVER use the Rear Window Defogger feature.  Even when camping...I generally wait a little before driving, and by the time I do there is no Rear Window visibility issue.  Just for fun a few months ago, I turned on my Rear Defogger Switch....and could see no indicator light....I distinctly remember (probably decades ago was the last time I switched it on) that it was bright!  Glowing amber, readily visible.  I assumed that heating element on the glass surface or the connector to the wires on rear window was funky, but since I never use it, I quickly forgot about exploring the problem.  I easily could have muffed up something when doing my occasional washing of interior rear window, or maybe just a corroded connector.  All of it is still a mystery for me.
Rich
San Diego

    On Thursday, April 2, 2020, 3:13:59 PM PDT, Alistair Bell <albell@shaw.ca> wrote:  
 
 My amber light is dim on both de frogger and fog light switches , for what’s that worth.

Alistair 

> On Apr 2, 2020, at 3:09 PM, Richard Koerner <rjkinpb@sbcglobal.net> wrote:
> 
>  I tried hooking it up as you suggested Mark, and got the same results as you; my drycell voltage was around 12 VDC instead of 9 VDC like your setup, and still the amber light is pretty dim, to the point of being unusable in normal daytime situations driving.  To keep things simple, I think I'm going to use the rocker switch without the indicator light.....one less thing to try and figure out 5 years from now when things stop working for whatever reason.  I tested everything indoors in a dimly lit room.....ya know, I originally thought that amber light was an LED but now I'm not so sure....may just be a light pipe utilizing a tiny incandescent bulb, like the bulb for the one nearby to help you find the switch on the dash at night.
> Rich
> San Diego
> 
>    On Thursday, April 2, 2020, 6:27:05 AM PDT, vw_van_fan_Mark <madvws@cox.net> wrote:  
> 
> I have 2 used stock switches in my hand.
> Testing with a 9 volt battery.
> Polarity doesn't matter to either light.
> The amber external light only lights when the switch is on and doesn't
> care which large pin has power. Switch off, light off.
> 
> I'm tempted to open one up.
> 
> Mark
> 
>> 
>> You'e working too hard.  What Dennis said -- brown goes to ground and
>> gray/blue (not blue/gray) goes to any gray/blue  wire under the dash.  That
>> will take care of panel lighting and and the power-on light.  Note that
>> power to the switch has to cone on the correct wire or the light will be on
>> constantly.
>> 
>> Yrs,
>> d
>> 
>