[reys21]

Replaced radiator, temp sensor, thermostat and all hoses. Checked the relays and fuses; all good. The only fan that come on is the A/C. I let the car run for a while but the main fan nevers kicks in. This is strange because the temp gauge seems to be working right. It gradually goes up until it reaches the middle and stays there.

 

[DavesSpectra]

Put a digital meter (under $6.00 at Harbor Freight) across the connector that the fan plugs into..If there is 12v across the connections then replace the fan...They do go bad.
Ebay has them for under $65 NEW replacements for OEMs
TYC 600660 Engine Cooling Fan | eBay
I have used TYC replacement parts and their quality is as good and better then original...
Dave

 

[reys21]

Took my car to friends shop. The fan on the A/C side is the one that comes on first. The radiator cooling fan on the return side was tested direct and it works but will not kick in at all. Im not sure if this cooling fan is the auxiliary fan or there is a problem with the wiring/computer. He also took some temperature readings and it never got over 179 degrees.

 

[wan]

i am having the same problem,The radiator fan is not working but a/c fan is ok.According to my KIA mechanic there is no 12 V coming into the fan,measured from the connector.He says if this happens then the next step is to check the fuse first then the relay.(located left side black box)If this does not work then the final thing is of course the ECU located under dashboard in front of the gear box.He says the ECU gives signal to to active the relays to turn on the fan.So all of them are related.I am most worried when he says that the final problem could be the ECU.Will post more after repair is done