Blower switch pigtail

It's a Packard 56 series connector, now Delphi...wait. Aptiv, it's Aptiv now

The Delphi/Aptiv part number for the housing is 12004327
https://www.mouser.com/ProductDetail/Aptiv-formerly-Delphi/12004327?qs=IZo/4GmaPbQcM/ZTPz6Z3g==

You have to order the terminals separately If yours can't be reused
Delphi 2989877 56 Series Female 12 GA Terminal 25 Pack [D56-2989877] - $10.25 : TheElectricalDepot.com!, Electrical Connectors and Much More!

I went that route because I've replaced quite a bit of the wiring harness on my truck

MEI 1055H is the complete pigtail
MEI-MEI Wire Harness for Kenworth Trucks - 1055H-1055H

Mine was melted when I got the truck six years ago. I didn't want to reinvent the wheel so I just replaced it with what was there. Add some conductive oxgaurd grease to keep the resistance low and maybe it will last a bit longer

 

I’d be tempted to run larger guage wire to it and a bigger fuse, bypass the connector or modify the pins with a more solid connection.

If it’s melted, at the plug, then I’m thinking a poor connection is creating heat.

 

worst case could use spade connectors n do individually

 

Freightliner has the same problem with bunk switch. The problem starts with the switch terminals getting loose on the switch. The arching causes the heat. Then melts the plug, once wires are touching in the plug, more heat. I thought It was the wiring getting hot, but after a year or two, had the same problem. Wires stay cool otherwise, with a new switch. Bottom line, cheap switch.

 

I had this problem on my last Truck, always thought it was a wiring problem, that took years to develop. Every junkyard Fld I’ve seen has the same problem. 2 yrs ago I replaced the plug harness and switch. I recently replaced the switch again, repaired and re used the melted plug for now. Nothing’s getting hot now. In my case at least, I’m convinced now, it all starts with the switch itself.