Odd radiator fan(s) behavior

["Craig D. Niederst" <niederst@telerama.com>]

My radiator fan(s) seem to operate at the exact opposite time I'd expect
them to. When I am moving (high or low speeds) the fan comes on full blast.
When I am stopped, it turns off. I replaced the thermoswitch about 3 months
ago, and the new one had a different part #, but the same temp ranges for
the different fan speeds. I ordered the part thru an Audi dealer (Langan in
NY, Osman's workplace), and was told the switch I got is a new pin # that
replaced the old one. Do you think this maybe the cause, or should I look
elsewhere in the cooling system? TIA.

Craig
'92 100S (73k)