Why doesn't Heater work in my Jeep Cherokee Sport?

Answer 1

That depends on what it is doing. If the fan is not working, it is the motor, fuse or wiring. The most likely cause of motor not working at all is the fuse. Second case is the motor. If the fan only works on high, the resistor block is bad. This is located inside of the air venting system. There are about four wires going to this resistor block. They ocassionally burn up.

Now, if the system has a fan, but no heat you have one or more of three issues. You are low on antifreeze, your heater core is blocked or your thermostat is stuck open.

Check the level of antifreeze. That is the easiest and most likely. If low, fill! If the heater core is plugged you can remove both hoses from the heater core and if you are cheap, like I am, connect your garden hose to the system for a few seconds. This blows the plug out ALMOST every time!

The thermostat will cause very little heat for a long time but of you run long enough you get some heat. They usually stick closed for me, but have been known to stick open.

I wish you well!