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Old 07-15-2018, 08:46 AM
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ala_xfire
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Join Date: Dec 2010
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Default Re: AC/Coolant/Radiator Combo HELP

Well, mostly. The FCM gets a pulsed 12v signal for the PTCM (ECM ) that tells it to supply X number of volts to the fan.
The shorted time between pulses, the faster the fan runs.
No pulses, no fan.