The fan has 2 speeds. You may not hear the low speed while driving since
it isn't as loud as high speed. If you have the lower grill off you can
see the fan temp switch on the driver side of the front of the radiator.
Pull the wiring connector off. It has 3 pins. On the wiring side, use a
paper clip or such to connect any 2 of the pins. Try all combinations,
of which there are three. One should make it come on low speed, one high
speed, and one won't do anything. If both speeds work with the jumper,
what speed does it sound like you were hearing while overheated? If you
think you were hearing high speed then how high was the gauge reading
when you heard it kick on?

Mark

Geneva Saint-Amour wrote:
> The gauge got to the top.  The red light blinked.  We pulled over.  The fan came on.  Just one speed.  The radiator is 3 years old.  The air is purged. We have a dash switch for the fan.Keep it coming.... I am a sponge, soaking up your information and ideas.
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