Fan blows fuse when turned on high speed

[crusin242000]

I need your help . I have replaced the blower motor , resistor and high speed relay. It blows when you switch it on high , any input is appreciated as this truck was butchered on wiring from previous work. Thanks


Sent from my iPhone using Tapatalk

 

[75gmck25]

Assuming an '82 is wired like my '75, is this the separate high speed fan fuse that is installed in a wire that goes across the firewall from the wire junction to the blower relay? Mine was the old barrel type glass fuse and it got so hot when the blower was running that it melted the fuse holder. I bought a 30 amp blade fuse holder and fuse to replace it and its been fine since.

 

[crusin242000]

I heard a pop. I will use my test light to search in the am. I am looking for areas to check and your input will sure get me started. The pop sounded like it came from the main panel under the dash by the drivers door area.


Sent from my iPhone using Tapatalk

 

[75gmck25]

On most squarebody trucks with A/C the lower fan speeds run through the switch and the resistor pack mounted in the plenum under the hood. The high speed connection goes through the blower relay and the direct power connection under the hood.

That A/C relay in the plenum allows a direct power feed, and also allows the system to automatically go to the highest blower speed when the dash control is set to max or recirculate position.