Recently purchased a 97 Grand Cherokee that had some front end damage. I figured it would be a somewhat easy fixer-upper... and the owner did mention that there was a loose ground causing the blower to randomly cut out while driving. He also mentioned that he would have to tap the wiring under the passenger dash with his snow removal brush and the air would start blowing again.
So after driving the jeep for a week I got a little tired of the air randomly not blowing until I moved the electrical connection around under the passenger dash. I decided to take the dash apart and figure out what the issue is. I pulled the connection apart and found that the plastic connection had some burnt charred plastic around some of the connections, looked like the main ground and positive wires on either end. I pulled all the wiring out and just connected them into each other to bypass using the plastic connector they originally fed into. After doing this everything seemed to work besides the HEAT! I checked the connections to make sure they weren't loose and even checked to see if the connection at the back of the Heat/AC controls were loose... and nothing.
The only thing I can think of is that some of the wires touched which blew the HVAC fuse a couple times wiring it together... so i'm thinking that maybe a relay or blend door maybe went out after this...? Right now it's blowing luke warm air depending on the outside air Temp and the A/C does work... but no heat at all. The box is warm also which i'm guessing means the heater core is getting hot. I also noticed that when I pulled all the wires apart from the connector that I was left with a white wire that did not plug into anything on the other side of the connector, so I electrical tapped it off so it won't touch anything.... just weird that there's a wire that doesn't serve a purpose.
UPDATE: I took the jeep to a trusted local shop and they mentioned that they could not understand why I am not getting heat since the heater core is getting hot and everything appears to be wired correctly according to the wiring schematic for the ZJ. The said that they were able to ground out the white wire that went to nothing and that they were able to get only heat to come out of the vents, however that is all I am able to get.... very weird.
Anyone have any issues like this or experience with these issues?