Heating Issue

Jeep_eh

New Member
Joined
Dec 18, 2018
Messages
8
Location
Toronto, ON
Hello all,

I've sifted (admittedly very quickly) through the forum for a solution but could not find anything helpful for my specific issue... Sorry if it's a repeat post!

It's starting to get a little cold where I am. I went most of last winter without any heat, but I'd really enjoy keeping the ol' toes warm this season.
Before I lost my heat completely, I could only get hot air at the max (4) speed setting. Now, nothing ... no hot air or cold air, on any directional setting or speed.
Just before I lost blowing air altogether, I could smell burning. Not too long after the smell, I lost all forced air (cold/heat)

Here is what I've noticed and done so far:

- I can hear the control switch working when I switch the directional controls. (ie, I hear sounds/movement when I switch the controls from defrost to mid to foot position). Which would lead me to believe its not a control switch issue?
- There is a very small amount of unforced hot air coming from the defrost on the dash.
- I've replaced the blower motor (Four Seasons FS 75712)
- I've replaced the blower motor Control Module / Resistor (Four Seasons FS 20275)

Beyond that, I'm at a loss...

Any help would be greatly appreciated!

Thanks!

2001 Jeep TJ Sport 4.0L - Automatic.
 
Considering you had a burning smell I would remove your center bezel and the temp control unit and check for any issues, there have been many cases where the harness/switch overheated.
 
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It seems that my Jeep is doing the same thing. I started a thread yesterday and I'm waiting to see if anyone responds on where to start troubleshooting. Those are the two parts that I was thinking is faulty with mine, but want to try to make sure that I replace the right part instead of throwing unnecessary money at my Jeep. Hopefully, we're able to figure out what's wrong. I am not as cold as you, but trying to drive in near/sub freezing temps is not fun without heat.
 
Mine does this about 1-2 times a year. The issue for me is the fan speed switch, every time. It will have a positive click when you twist it, even though it’s burned out. I’d remove the items TJ4Jim recommended, pull the electrical connector off the fan speed switch, should be a bit melted if it’s the issue. Be sure to check the plastic clip on the wiring harness end as well. Hope you figure it out!!
 
Start with the fuse, swap relays, check voltages.

78183
 
Are the rubber line# getting warm when the rig is at running temperatures?

Thanks for all the info folks!

I'm not sure what you are referring to in regards to rubber line# getting warm?
I plan on checking the switch this week - will update.

It's been a cold winter ... brr.
 
If the to hose going into your heater core is hot and the bottom is cold, is that an indicator that the heater core is plugged? Other then that everything else works fine, just no heat. Thanks.