Jim Grant's Tech Tips
'97 Chrysler
Town and Country, No cooling fans
Q:
The cooling fans just stopped working on my ‘97 Chrysler Town &
Country. The first time I noticed the problem was driving in town and
the temperature gauge started to climb into the hot zone. The only way
I could even get the temperature to drop was to turn the heater on full
blast. As soon as I got back out on the highway the temperature returned
to normal. When I got the van home I found that when the A/C was turned
on the cooling fan did not turn on. The cooling fan had always come on
when the A/C was turned on. I allowed the engine to idle until the temperature
gauge was almost into the red and still no cooling fans. I’ve checked
the fuses and the connections to the fans yet I can find no reason for
total failure of both coolant fans. Do you have any ideas?
A:
Your Chrysler product has a broken screw. Yes, a broken screw. The cooling
fan relay for your vehicle is located down on the frame/uni-body to the
left of the radiator. Just behind that revengeful air cleaner box that
someone who claimed to be an engineer designed. This cooling fan relay
looks nothing like one, it has a heat sink incorporated into the relay.
The problem we see most often is one of the screws that hold the relay
into place breaks off. The job of the screws that hold the relay are two
part. One, to hold the relay in its hiding place and 2 to keep the heat
sink in contact with the frame. The relay which is computer controlled
manages the electrical power supply to the cooling fans. Electric cooling
fans use a lot of electricity which translates into heat. For the relay
to survive it has to rid itself of this heat. Which explains why the heat
sink is held against the cooler metal of the vehicle frame. It seems the
screws that were used to hold the relay in place are not of the greatest
design, the heads just happen to snap off. Once this happens the relay’s
heat sink is no long in contact with the frame and the relay over heats.
The relay fails in one of two ways, either the cooling fans turn on full
blast and will not stop or they will not turn on. The fix is a new and
improved relay with new and improved screws. By the way the relay has
been updated at least three times and the last time I called in an order
for one they had over 20 in stock. Does that tell you anything?
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