Check my post on 4x4 forum. This has just happened to me and the problem is the blower resistors module which is located behind the glove compartment. You'll see a connector with 5 blue wires. Pull back the red tab, push on the connector release and pull it out of the module. Then, remove the 2 screws from the module (8mm) and remove the module which is just a pc board coated with black epoxy. You must have a trace burnt like mine. I did some research and discovered that the Sebring had the same problem we had with the resistor module and they had an upgrade. The good thing is that the resistor module from the Sebring is interchangeable with ours. That's what I did. The p/n from the oem p/n for the liberty is 5139719AA (Airtex 4P1338) and the Sebring p/n is 5174124AA (Airtex 4P1326, Standard RU347).
That's what happened to your board:
http://img341.imageshack.us/i/2002sebringheaterresistec7.jpg/ and that's the improved version for the Sebring:
http://info.rockauto.com/Airtex/4P1326.jpg. To me, the improved version is a lot sturdier.