My lexus es300 2003 model cooling fan dosenot starts when i start the engine. But when i turn on AC both the fans are working. Please guide me how does it works?

Asked by Apr 10, 2015 at 04:44 AM

Question type: Maintenance & Repair

1 Answer


The engine cooling fans turn on at a set temp, depending on what the factory set it too be. Some turn them on at 212 degrees F I have seen a few that go higher up 220 degrees F. A/C overrides the normal system and turns on the fans to provide extra air flow to cool the refrigerant from the A/C system. HTH

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