Jeep Cherokee XJ Blower Motor troubleshooting

How to get air flowing again in the HVAC system.

The blower motor stopped running during my last off road trip past winter. Today I decided to find out why and get it going again.

I started by checking the blower motor itself. Last fall, squirrels had chewed the wire and I had to make a splice. The wires were intact so I connected 12 Volts to the terminals. The fan ran. So that part was good.

Next I checked the fuse. Due to my roll cage and racing seat, this is no small task. It requires a lot a flexibility that I need to work on again. I eventually got the fuse out and it looked pretty rough.

But the voltmeter showed ti still worked. I replaced it anyway. I also sprayed some contact cleaner in the fuse block terminals. The fan still did not work.

Next, I pulled the dash panel to access the switch. I first tried to just wiggle it out some and get to the blower motor switch. I have a winch control panel mounted where the radio used to be so I was trying not to have to remove that.

The wiring diagram said power came in on the blue wire. But there was not voltage there. I was getting closer. I was also happy to see the plug on the blower switch was not melted like they usually are in Cherokees.

Next I pulled my winch control panel so I could get to the other connections and test the power coming to the main switch in the HVAC controller.

I soon found my problem. The main power harness was not connected to the back of the HVAC controller.

While it was loose, I checked to make sure the violet wire had power and it did.

I plugged it all back together and heard the whirr of the blower motor. Now I can have heat and defrost again!

I also can make the electric radiator fan kick on by selecting AC even though I no longer have a compressor.

XJ Blower motor