marly

I have a 2011 Ford FX4 150. My fan stopped working so I thought the problem was the Blower Speed Motor Control Module. This morning I pulled my Blower Speed Motor Control module out of my truck and I found that it melted the wire harness.

My next question is, what should I do? I’m pretty concerned that it melted the harness I was hoping I could just replace the control module, but it looks like a much bigger job.

SUPERLOOP

You can buy a replacement pigtail and splice it in your harness. The Motorcraft number is WPT-688. It's a plug with usually around 6-8 inches of wire, crimps, and heat shrinks.

Jermsy

you're going to need to replace both sides but before you do - pull your steering column apart and check your ignition switch to make sure it isn't burned up. Most of the blower motor problems I see are caused by bad ignition switches.
Check the ground on your battery to make sure it's good.
I'f you've had any aftermarket stereo, remote start, alarm, etc. work done - check the connections for shorts or exposed wires.