I have an 05 v6 mustang and I just replaced the water outlet housing. Because it cracked on the side and water was coming out the back of the housing. Now my coolant fans won't come on, only when I run the ac. What could be the problem? I have changed the coolant temp sensor, and the thermostat.

SOURCE: fan won,t run on 2000 Ford Contour

fan motor may be bad. also could be a sensor. you can jump the fan motor off of the battery to see if it works.

SOURCE: 98 Mustang v6 - no AC

Make sure the radiator pressure cap is the correct one and that the hose is not soft--check the lower hose and heater hoses for softness as well. They should be firm, but not hard or cracking. The temperature sensor is reporting normal operating temperature, so it and the thermostat are working correctly (hot water would blow out of the radiator if it were stuck). Check the cooling fan for free turning and no noise. Check it's grounding connection. Check the fuse box for blown fuses to the fan and to the A/C compressor. Make sure all the relays and fuses are firmly pressed into their sockets. Check the A/C compressor clutch winding for resistance--should not read infinity. Does the blower motor for the heater/A/C run when either is turned on? The A/C switch on the dash may be defective.

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SOURCE: Son has a 1997 contour with 2.0l overheated

hard to get to and difficult job...are you sure you dont have cracked head? is there water in the oil....does the oil look milky? look in the radiator is there oil residue in the coolant........