Bought the xj about 3 weeks ago and although I hadn't driven it much (turning wrench), I never noticed any blower issues. When I got in the XJ to drive to work this morning, however, the heat wouldn't come on and I couldn't get it to blow any air in any direction. THankfully, the jeep warmed up enough that the heat finding its way out of the defrost vents gave me a slight window of clear on the windshield to get to work.

What are my differentials and how do I check them? I was fiddling with the stereo above it rewiring it, but I didn't notice any way I could have messed with the heater controls from there, but I'll check for anything that looks off this afternoon. What else should I look for? I heaer that our rigs tend to have blower issues? How do I doangose that?

Thanks,
s

 

does it work on high?
could be the blower motor resistor.

 

It does not blow at all no matter where the dial is. I've done the resistor thing on my Focus a while back, but this is like the heat ***** and dials are just for looks.

s

 

If it's completely dead, I would start with checking the heater blower fuse. If that is bad you probably shorted it while fooling with your stereo wiring. Swap it out and it should work.
If the fuse is good then I would look behind the heater control panel and see if anything was fried while messing with your stereo wiring.
I've found while fixing aircraft cockpit electronics for 22 years, that 9 out of 10 electrical problems are caused by people fooling with wiring that isn't broke rather than regular old vibes or corrosion.

 

I totally agree with you that I probably did it when fooling with the stereo. The unit was wired incorrectly from the PO and I had to rewire each wire at a time since the dork cut out the connector from the wiring harness. I did all of this with the negative battery cable off though, so I tried to minimize damage issues, but there was a lot of pulling the stereo to check connections prior to pulling the neg cable. the stereo has its own fuse on it, so I assumed that that fuse would go first. Guess not (I'm no electrician). I'll make sure to check the fuses and any obvious wiring concerns that I can see after pulling the stereo.

Where else should I look?
Thanks,
s

 

I would check the wiring under the cd player. It didnt take much to unplug mine when I installed a cd player. Check that first, I always check where ive been before making any other moves to check parts. Kinda my rule of thumb

 

Thanks is my plan and I'm glad to hear that it is easy to happen when you're dinking around right above it. I'd love for this to be an easy fix (no jinx). Do you remember off hand which end of the heater contol had the plug in it? I'm really cramped for space since I cannot easily unplug the stereo (all wires with individual bullet connectors...I know it isn't the best method, but I'll probably swap out the stereo at some point).

Also, do you have any other ideas if that isn't the problem? I plan to check fuses and pull the stereo to see if I unplugged the heater control, but if that isn't it, where should I start looking?

Thanks,
s

 

does the speed adjustment for the blowers work (can you hear air get stronger or weaker when turning the know but no air comes out) or is it both the speed and the adjustment for where you want the air to blow (leg, face or defrost)

 

The heater controls are absolutely non-functional. I get no air (hot or cold) coming out of hte vents and there is no sound of air (like the blower is working but failing to push air out). My Heater controls operate the same with the car not running. I can turn the dials but nothing happens whatsoever.

s

 

Check fuses first.

Pull your dash bezel off and remove the 4 screws that hold the HVAC controls.

Carefully pull it out and inspect the wire connector to the BLOWER SWITCH.

The switches have a tendency to short out and melt.
If you can, pop the connector off and inspect the terminals.

Had the switch go in BOTH my XJ's (91 & 96)
Junkyard run for used switch netted me TWO, out of the 8 I pulled.
The other 6 were fried.

 

Awesome. Thanks for the to-do list. I'll get to that right away. The local junk yard only has older XJs. Do you know what years have swappable switches?

Thanks,
s

 

what year xj?

my tj has the problem you are describing. it is a 99 and has round dials.
they're known for melting the wire connector on the back of the hvac head unit.
i have cut my melted switch off and crimped on some spade connectors and installed those into a new head unit, protecting them with some electrical tape so they won't short out again.
btw, the connector isn't available from the dealer, or anywhere for that matter. have to find one at a wrecker and snip it out and splice it in yours.

the round dials started in 99 for the tj's. probably the same for the xj's. those are interchangable up to 2003 for the tj's, so probably good up to 01 for the xj.

JP magazine did a write up about this a couple years ago.
they said to use a resistor for every speed.

when mine craps out, i just reach in through the glove box and feel for the wires that go into the rear of the hvac, and wiggle them around until my blower works. try that.

 

And the trophy goes to...(drum roll please)...Mudhunter.

I pulled the heater head unit and sure enough, I had accidentally unplugged one of the connectors. What a simple fix! I do appreciate the heads up on the melting switch issue. I'll have to pull the connectors off of a j/y jeep next time I'm out there. I'm limited on the jeeps available, but if the connectors look the same, Ill grab a couple.

s