Hi,

[EDIT: Short version--does the fan on the fridge get power when the 12v is
unplugged but the fridge is plugged into, and running on, AC power?  That's
what I want to know, details are below.]

I've done a bunch of the refurbishment/improvement stuff that you can find
in various places online, and my fridge seems to be working pretty well.

The last thing I want to do before putting it back in is to hook up an
external and internal fan.

The fridge is on a workbench, and I plugged it into AC power.  Here is a
picture for reference:

http://imgur.com/rrB9Ayd

The yellow and blue wires lead to the stock fan.   One wire (I think the
yellow one) goes to a thermocouple that completes the circuit (and turns
the fan on) when the heat-dissipating fins on the back of the fridge warm
up.

However, under AC power, I'm not detecting a voltage on either the blue or
the yellow wire.

If I'm understanding how the fan works, one of those wires should be
constantly at 12v.

However, I don't know if this is true when it's only plugged in to AC
power.  Maybe the fan is powered by the 12v connection even when the fridge
is switched to be running on AC?

So....that was a long way of asking that question, I'll put the question at
the top now.

mike