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I have a 2000 Bonneville SSEI and when I turn on the A/C, the fans are not turning on .. checked the Relays and there good .. When the engine gets to normal temp the fans turn on .. any help here .. Thank you

I'm not sure that the fans are supposed to turn on until the temp gets high enough for them to warrant it..the computer controls the fans thermostatically ( sends the signal to the relay to turn them on ).

With the engine up to temp, when you turn on the A/C, the cooling fan should turn on right away. Can you verify that this is happening first? Perhaps someone in a warmer climate can verify operation in their car....Can't do much up here in the Arctic of MN at the moment...we just went from 60 to winter in less than 24 hrs...

the fans do not turn on when the a/c turns on .. the relays are good .. that's what I cant understand

Can I assume that the Compressor actually is turning on and provide A/C? I'd be checking for voltage on the trigger side of the relay to see if it's getting the signal, or listening to it to hear it click as you turn the A/C on and off. If the compressor is turning on, then I would think the fan relay is getting power sent to the trigger side of the relay ( marked 85 on the relay )

Pretty sure that one uses a pressure sensor in the high side line that tells the PCM that the pressure is high enough to turn the fans on. Low ambient temp, or low charge may not build enough pressure to kick the fans on.

yes, please be sure the a/c is engaging compressor - when my freon was low, the fans wont engage cause compressor wont spin - charged system and all is good

for a quick test of the fans, you can unplug the coolant temp. sender( below thermostat housing
this will trigger both fans into high cool.

Was told today the Compressor is shot.. you can turn the a/c on the clutch turns on but not cold .. compressor making noise and its fully charged .. maybe that's why fans don't turn on when compressor engages.. its bad