Fan speed #3 stopped working

sergioemz

Member
Joined
Apr 28, 2023
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27
Location
Mexico
Hello!, my fan speed #3 on my tj sahara 2001 went out. I had the A/C on working just fine but suddenly started smelling something burned (like wire), then smoke came out of the vents, turned the A/C off for a while and when turned it back on speed 3 was not working . all other speeds are working fine. tested the fan switch on the temperature panel and that's not the issue.

on an additional note, now, when turning the A/C off, I hear a funny noise like coming inside of the center panel, I don't think it was doing that before.

Maybe blower motor going bad?
 
In my opinion, your motor has failed. Due to age, friction, wear, and who knows what else, your motor has now exhibited a higher load to your electrical system. This condition invariably results in the failure of the resistor based voltage divider used to control fan speed, associated wiring, and possible the switch used to select fan speeds.
Don't run your fan until you get this fixed.
Get a new fan and a new resistor pack.
Good luck!
 
The burning smell may have been from the wires that plug into the blower resistor melting, I had the same issue and it sounds like its a common symptom of the blower motor going bad.

Also the early model tj use a different style blower resistor than the one pictured above
 
Thank you all, I already ordered new blower motor and resistor. will be replacing them early next week and let you know the outcome
 
I recommend looking to verify the wires/plug are in good condition. That way you can also get those parts if neeeded. Photo shows what mine looked like, the entire left side of the plug got melted

20230306_153033.jpg
 
yupp, resistor plug is fried. do yo recommend to change the blower motor to although it has no visible damage? just for the sake of time?

resistor.JPG
 
Blower motor going bad is the cause of voltage spikes which causes it to melt. So yes, change the the blower motor at the same time
It's not really voltage spikes that is the problem, it's a significant increase in the current the motor is drawing after its motor windings start shorting together. That increase in current can take out the wiring, resistor pack, and even the fan speed switch sometimes. The motor windings are wound with bare copper wire that was insulated with shellac. When the shellac starts breaking down and flaking off the windings start shorting together.
 
It's not really voltage spikes that is the problem, it's a significant increase in the current the motor is drawing after its motor windings start shorting together. That increase in current can take out the wiring, resistor pack, and even the fan speed switch sometimes. The motor windings are wound with bare copper wire that was insulated with shellac. When the shellac starts breaking down and flaking off the windings start shorting together.

would it be ok to weld the cables into the new resistor? It seems it's not easy to find a new harness in my contry
 
I spent a considerable amount of time on my blower motor issue and learned a lot along the way.

1. What Jerry says is right. Crimp on connectors are a better choice. .187" female spade terminals are the right size for that connector IIRC.

2. The problem could be the blower motor. However, I tried 2 new Mopar blower motors to fix my wire overheating issues. The first pulled 24 amps and the second did the same. At that point, I knew it wasn't the motor

3. The stock blower motor wires (all of them) are undersized for the vehicle. Over time, they get worse at carry current due to oxidation/ corrosion etc... This was my problem. Ypu will need to do a voltage drop test between each leg to see if the wires are your issue. Turns out I was losing several volts in the last leg of the positive wire to the blower motor.

I ended up completely reconfiguring the wiring. What I did is fully explained in another post on this site. I have no issues anymore. Wires stay cool and blower motor only pulls 12-15 amps.

This was one of the least fun things I did but I have great AC and heat now so was totally worth it
 
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