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Old 07-09-2011, 08:17 AM   #3 (permalink)
nemo
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Quote:
Originally Posted by Galane View Post

There's a 4th relay in parallel with the AC clutch and the low speed relay so the fans run in low speed when the AC is on.

I used a pot of water on my stove and a battery charger to calibrate the high and low settings. Low turns on at 190F, high at 200F. The engine thermostat is rated at 195F, so soon as the thermostat opens the fans come on low speed.
Why the choice of low speed at 190F? I would have thought you would want to set it a bit higher, above the thermostat say 200F. And for the high speed say 205F. Do you know what the normal operating range is for you engine?

On my car (06 GP) the operating temperature range 194 to 225. The cooling fans with the air off won't come on until the temp reaches 220 degrees then turn back off at 197 degrees via the u gauge.
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