>    As expected, the LED lit brightly when the fan was energized
> and  mashing
> the button forced the fan on. The unexpected result was; as you started to
> drive, air flowing through the radiator made the fan's propeller rotate.
> This caused the motor to act as a generator and produce voltage, in turn
> illuminating the LED to about half brightness.
>    Benefit? As long as the LED glows at any speed above 15mph you know the
> fan's bearings have not bound up! QED.

 You know, I bet if someone took all the various indicators, switches,
gauges, and buttons we've all collectively added to our vans and equipped
one van with all of them, they'd end up with a really cool control panel ,
like the nav/engineer panel  on the right side of this photo of the cockpit
of a C-141:
<http://tinyurl.com/2x4ps7>

Personally, that is my goal...

--
John Bange
'90 Vanagon - "Geldsauger"