Radiator fan not working when car heats up fuses are all good for a 2002 chevrolet malibu

there is a seperator valve under the hood it mite be faulty. or could be ththe air seperaitor under the dash .this is the door that controlls where youre car draws air from..eather cold air or air heated by the heater core.wich may also be youre problem.there is multible things that could cause this problem .hope this helps you good luck

yes it does, check the relays to the fans, and also the fuses, they should be in the under the hood fuse box, once you determine that the fans work ( turn on the ac and see if it starts it should ) you can move that relay to the normal fan relay spot, ( if you have 2 fans ) if your car still over heats after knowing the fans are working,, check the thermostat

fans for heater fans for cooling on the engine need more info

Blow out the radiator core from the engine side with compressed air to remove bugs and other debris. Make sure the cooling fan comes on when the engine gets to operating temp. If the car car has AC, turn it on which should start the fan immediately. If no fan action, try to turn the fan blade(s) which should turn easily with no noises. Check the fan fuse and fan relay. If the fan(s) come on fine, check the coolant level in the radiator core--it should be right at the top. Check the seal on the cap and replace it if it is decayed or damaged. Make sure the reservoir bottle is filled to the line and the connecting hose is in good shape. It is possible that the thermostat is sticking and not opening fully. Also, check the intake and outlet hoses to and from the radiator for firm condition without decay, collapse, or other damage. A hose can sometimes peel away a portion of the hose interior which can cause blocking. Hope some of this helps!

check to make sure fans are working for radiator. if not check coolant tempurature sensor, fuses, and relay. is all air out of coolant system!

is electric radiator fan coming on? if not the relay or fuse is bad

Check the cooling fan, its sensor, the relay, the fuse. On most cars the fan is not needed on the highway, but engine overheats it it doesn't switch on inside the city. Also, clean the system with a special liquid according to the directions on the can and use coolant after that, water causes corrosion. While pouring/filling/cleaning, keep the heat switch on max heating to allw circulation via the heating radiator.

check the fan relay in underhood fuse box. and also the fuses.

Fill over flow bottle right to the top and run engine....watch for bubbles.
If you see bubbles you may have a bad head gasket or a possibly a cracked head.

This allows combustion gases into the cooling system and the system just can't dump that amount of added heat.

sound like a warped head, cracked head, or a head gasket. Have the radiator pressure tested and check the engine compression. As for the fan check fan relay and fuses other than that could be wiring or bad fan motor.