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RE: Changing 5KT afterrun fan time limit

Richard wrote:

	>1 Are there 2 fans?  The regular fan -- and an 'afterrun' fan?

There's only one radiator fan and motor. It has several modes of operation,
though. With ignition off, when coolant temperature reaches preset value, a
separate thermoswitch located at the back of the upper coolant flange causes
the fan to run at low speed. The electric coolant pump should run at the
same time. We like to call this mode of operation an "afterrun fan".
With the ignition on, the same fan will run at low speed whenever A/C is on,
it will also run at medium speed when triggered by the radiator
thermoswitch. If the engine gets really hot or refrigerant pressure is too
high, the fan will run at high speed. 

	>3. If there are 2 fans, and the afterrun fan doesn't work -- does
	>regular fan come on instead after driving?

With ignition off, only the afterrun mode is operative. So, the answer is

	>4. Would the car let me know if the afterrun fan doesn't work?


	>5. If it appears as though my afterrun fan isn't working -- how can
a I
	>check to make sure?

At the back of the upper coolant flange there's a thermoswitch with two
spade connectors. With the engine off, remove the wires from this sensor and
short them together. The fan should run. If it doesn't, then you have a
problem. If it does run it's generally OK, provided the thermoswitch itself
is good.

	>6.  IS this normal in the cold weather?

Yes, to some degree. Whether the fan will run and how long depends on both
the weather and the driving style. In winter after 20min drive to work in
the city my fan usually won't come on. In summer, particularly after some
"spirited driving" or driving through traffic jams with A/C on the fan would
run every time for 15-20 minutes, killing the battery.

Aleksander Mierzwa
Warsaw, Poland
87 Audi 5000CS turbo (mine)
88 Renault Medallion wagon (mom's)
91 mountain bike (just in case both cars broke at the same time :-)