HVAC blower not working

Z3k3Z

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Original poster
Joined
Mar 16, 2021
Messages
6
Location
Long Beach, California
99 Jeep TJ

The problem began with the Fan Speed Switch dying...I replaced that. Worked fine. Then it died again. So I bought another switch. Plugged it in and nothing happened. I began to read forums and discovered the dreaded damndable TJ Blower problem. Everyone suggests it could be the relay or the blower fan. So I replaced both of those.

So now I have a new relay under the glove box (I cleaned out a forest of dried leaves just behind it). I have a new blower motor. And when I went to turn the fan on and up...nothing. Tried putting in the brand new switch. Nothing. Tried the old switch I never threw out. Nothing. Fuses are all fine. Can't find any melted wires.

Could I have killed the brand new switch that quickly?

What do I do now? What is the next step when you've replaced everything that could be the problem?
 
Have you taken a look at the HVAC mode selector? The ground on the blower switch runs through the mode selector before going to vehicle ground. I pulled mine yesterday, the connector was melted on the inside, and the vacuum selector itself had heated up so much it melted and cracked the housing. Couldn't really tell either before I pulled it
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hvac diag 2000TJ.png



You can try testing the replacement blower speed switch outside of the vehicle (to make sure it didnt go bad already or DOA) with a multimeter set to resistance. With the 5th lone pin facing to the right, the pinouts go

2000 tj blower speed switch.png
 
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Have you taken a look at the HVAC mode selector? The ground on the blower switch runs through the mode selector before going to vehicle ground. I pulled mine yesterday, the connector was melted on the inside, and the vacuum selector itself had heated up so much it melted and cracked the housing. Couldn't really tell either before I pulled it
View attachment 234920

View attachment 234921

View attachment 234922


You can try testing the replacement blower speed switch outside of the vehicle (to make sure it didnt go bad already or DOA) with a multimeter set to resistance. With the 5th lone pin facing to the right, the pinouts go

View attachment 234923
Thanks, found it. Funny, I have the exact same pictures.
 
Thanks, found it. Funny, I have the exact same pictures.
Sweet. Glad you found it. I’d believe it if you told me you snuck into my Jeep and took those pictures! I believe the middle wire is the one that runs from the ground pin on the Fan Speed switch.

Here’s the Mopar replacement for that switch if you need it. Mines a 2000 but I think it’s the same part number

https://www.amazon.com/dp/B004E3D66E/?tag=wranglerorg-20
 
Sweet. Glad you found it. I’d believe it if you told me you snuck into my Jeep and took those pictures! I believe the middle wire is the one that runs from the ground pin on the Fan Speed switch.

Here’s the Mopar replacement for that switch if you need it. Mines a 2000 but I think it’s the same part number

https://www.amazon.com/dp/B004E3D66E/?tag=wranglerorg-20
Did you find the 3 pin connector anywhere? Or a repair kit?