Melting HVAC wiring!

[TinyTJ00]

Fan speed went out today. Only high speed worked. Then i started smelling burning electronics today while the heater was on. Found out why. The wires were hot to the touch. But see, it's not the fan speed that melted. It's the ON/air flow direction dial. Does it matter?

I replaced the blower motor and resistor a few months back. Now to get new plugs for the harness and perhaps a new HVAC control. Yay 21 year old rigs.

Should I replace the plug AND the HVAC controls? Or just the plug...

Thank you

 

[Jerry Bransford]

The fan motor was the root cause of the damage. I'd replace everything that shows signs of being burnt or melted.

 

[TinyTJ00]

The fan motor was the root cause of the damage. I'd replace everything that shows signs of being burnt or melted.

Only thing that showed signs was the one pictured above.

I replaced the burnt plug with one from pull apart. Same issue as before, blower speed works only on high. I left the heater running for about an hour. No burning smell and the wires were not warm.

So having already replaced the resistor AND the blower motor about 4 months ago, I'm left with having to replace the whole HVAC control unit. Going to the pull apart again on Friday and grabbing one and any other random parts I may want for my TJ.

I'll update this thread after the new unit is installed.

 

[P man]

You need to check all wiring that goes to the control unit and also to the resistor. These jeeps love to melt wiring and I'm guessing you just haven't dug deep enough.

Also don't rule out the blower motor they can cause issues with age