I've tried everything and still blowing fuses. The relay on a 90 xj is under hood on passenger side on fender well under a plastic cover.

 

What is the function of this relay?

 

honestly no clue... I guess sort of like a fuseable link to break the circuit when ac isn't on. And sorry it took me slow long to answer. Still trying to work on it and figure out how to reply and answer in this forum

 

Here's the 1990 HVAC blower circuit diagram. Not shown is the AC side of the circuit which would include the compressor clutch, its relay, etc. The AC side is also powered from the same fuse as the blower.


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This is what a melted blower speed switch connector looks like.



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Back of the HVAC climate control panel.