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Radiator Fans not spinning (radiator boiling)

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19K views 14 replies 5 participants last post by  MrMegee  
What I would do is with the car running. Unplug the coolant fan temp switch on the bottom passenger side of the radiator. Jump the wiring harness pins together with a paper clip or a small length of wire. See if the fans come on. If they do then replace the rad fan temp switch. If they don’t then check the fuse as I showed you above. If that is NOT blown then move to the three relays. They should make audible clicks when you test them. You can test them by pulling them out and apply voltage directly to them to listen for a click.
 
There should be a 30amp RDI fuse and a 30AMP CDS fuse in the main fuse box by the battery that both need to be hood.

just a last thought if after you tested all of the above, it’s pretty rare but it can be a possibility that the fans themselves are broken.

So after you have tested all of the above and you know everything is working correctly (jumping fan switch, replacing fan switch, testing relays, checking fuses)
And the fans still don’t turn on, apply power directly to the fans to make sure they both work.