Relationship with TJ currently on the rocks due A/C electrical issues

TJ Starting

TJ Starting

The Seven Slots of the World
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SE TX
Seems TJ has been throwing a tantrum lately but I believe this is one of the last issues to be taken care of so far. Please excuse my illiteracy with electronic systems, I'm sure for some of you this is a very easily diagnosed problem. So thats why I'm here.

Ok, so if I have this correctly in my head,,, A couple weeks ago the blower motor started only worked on high, so I finally got around to replacing the blower motor switch. Tested it and everything seemed to work great. Next day when I left for work I got nothing. No blower fan whatsoever. I'll add here that when I replaced the blower control switch I noticed that the plug was pretty melted, now when I went to also replace the relay and resistor, I noticed the resistor plug is also melted. See pics below.
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(Recap, replaced blower motor switch, blower motor relay, and resistor. Still no blower action. Considered replacing blower but have currently decided not to due to the melted plugs.)
 
I’m no ace on all that but hear those get really hot- I got a whole new assembly for my 06 at Autozone or Advance for $150-

Let us know how it goes, lord you need air right now.....
 
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AndyG said:
I’m no ace on all that but hear those get really hot- I got a whole new assembly for my 06 at Autozone or Advance for $150-

Let us know how it goes, lord you need air right now.....
Click to expand...

Yeah AC on the way home from a hot day is a must right now. You mean replaced the whole hvac control assembly?
 
TJ Starting said:
Yeah AC on the way home from a hot day is a must right now. You mean replaced the whole hvac control assembly?
Click to expand...

Sure did - was sort of clueless and didn’t know some parts were even sold separately-

The only snag is the selector for the vacuum lines had to be reused on mine because their is a diameter change in 06 - weird. It just snaps in.

I go from loving mine to wanting to push it off a cliff regularly.
 
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When I bought my TJ, the only receipt for service the PO had was paying a shop to replace the pigtail on at least one of the blower motor connections.

Even if the melted connector wasn't actually the root cause, it's gotten hot enough now that it's not going to hold a proper connection and will continue to cause more problems.
 
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IOwnCalculus said:
When I bought my TJ, the only receipt for service the PO had was paying a shop to replace the pigtail on at least one of the blower motor connections.

Even if the melted connector wasn't actually the root cause, it's gotten hot enough now that it's not going to hold a proper connection and will continue to cause more problems.
Click to expand...

I'll see if I can find some replacement plugs.
 
Ok, I am going to chime in with hopes that someone corrects my assumption because I would begin to look for a faulty ground?
 
TJ Starting said:
considered replacing blower but have currently decided not to due to the melted plugs.
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Are you able to check the draw of the fan motor. I seem to recall reading that when they get old they start drawing a lot more power causing connections to melt.
 
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L J said:
Are you able to check the draw of the fan motor. I seem to recall reading that when they get old they start drawing a lot more power causing connections to melt.
Click to expand...

Not exactly sure how to do that but I'm sure I can figure it out with some YT.
 
Should I just put a new blower in and see what happens? I was just kinda worried about burning it up considering the burnt plugs. I don't have a multi M with clamp but I think my dad has one I could try.
 
Electrical problems are no fun. At least when the engine blows up or the axle dies you can pull it apart,actually see the broken part, and replace the busted piece. You just can't normally see an electrical problem. It often requires meters and test lights to fix, and if you don't know what you are doing, you can do more damage than good.
 
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I would be looking to replace the blower motor and all the burned/melted connectors.
The issue is usually caused by the old/worn/tight blower motor. As they age/wear they start to draw more amps, usually melting the blower switch and connector. Also look at the blower motor and the resistor connector. they also have a tendency to melt.
 
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The cause of melted wiring, melted connectors, burned up resistor packs & switches etc. is the fan motor having gone bad and shorting out internally. I'd definitely replace the fan before trying to repair anything else.

The wiring used for the motor's windings are insulated by shellac and when the shellac starts breaking down the windings start shorting together causing excess current draw through the fan control circuit.
 
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Two weeks ago our switch went out in Bullhead City. the AC still work but only when moving;
It was 106 out and a 3 hour drive home.
Not so much fun it was cooler but not cold in the LJ.
The only saving grace was it happened at 6pm not at noon
I replaced the switch but also put a bypass switch so that if the switch ever failed I could simply unplug the hot lead to blower and plug in the switch.
A flick of the switch and fan blower on High AC blowing Ice cold again.
 
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JPHikr said:
Two weeks ago our switch went out in Bullhead City. the AC still work but only when moving;
It was 106 out and a 3 hour drive home.
Not so much fun it was cooler but not cold in the LJ.
The only saving grace was it happened at 6pm not at noon
I replaced the switch but also put a bypass switch so that if the switch ever failed I could simply unplug the hot lead to blower and plug in the switch.
A flick of the switch and fan blower on High AC blowing Ice cold again.
Click to expand...
Keep in mind that as described just above above it's highly likely the fan motor itself is the root cause of your problem.
 
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Thanks for the help and ideas guys. As of now case is closed. Found these spade connectors weren't making connection. They just fall off but hold them on and everything seems to work fine so I'll be ordering a replacement plug for that as well probably replacements for the other melted ones. Also got a new blower that I'm gonna install on yalls recommendation.
20220709_122558.jpg
 
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