Cooling fans are easy to troubleshoot. Some automobiles use two smaller fans or one larger fan. The twin electric fan set up will use one fan for cooling the engine. The other fan will be used for cooling the air conditioning and radiator but only works with the ac on. Never continue to run the vehicle up in the red temp zone or you can cause severe damage to the engine. First do you have a temperature gauge in the dash? Is it working correctly?
Lift the hood and verify visually that the fan is not working. Does the car cool down once you drive up the highway at 40+ mph? If not, you may have a thermostat sticking or low coolant. The thermostat can cause the engine to stay hot. This can also be the problem if the gauge stays low and the car never heats up. If the temp gauge is reading low yet the two radiator hoses are warm, the temp sensor may not be working. There may also be two temp sensors or senders, one that controls the gauge and one to switch the fan on. If the temperature is getting high and the fan still won't come on you may have a fan problem.
First check the fuse to the cooling fan, if bad, replace it. When the car is getting hotter than normal and the fan should be on, unplug the fan wire. The cooling fan wire will have two wires positive and negative, and should be putting out 12 volts dc. If there is no voltage check the wires and the fan relay. The cooling fan relay is usually under the hood. If there is voltage running to the cooling fan, you probably have a bad fan. You could try jumping wires to the fan directly from the battery, but there is no need if there was voltage there.
Cooling fans can be purchased from places like autozone for aftermarket or factory replacements from a dealership. If you decide to use aftermarket measure the dimensions first. Then check the fan to verify that the cfm rating is high enough for your type of engine. Also make sure the wires for the electric fan are to the correct polarity. If not it wont damage the fan but will spin backward. The fan should pull air from the front of the vehicle and push it out through the radiator.
Jerry Lemke is the author of http://www.freeengineinfo.com A site dedicated to repair and information on all types of vehicles.
