I need to wire a radio to a 2010 freightliner cascadia plz help

One wire on the harness goes to your dash light dimmer switch. You probably have that wired wrong to the stereo. Now-a-days they make adapter plug ins for most vehicles where you don't have to cut the harness.

What stereo and model is it and I'll see if I can find the truck wiring diagram.

 

You don't need to cut and hack your wiring Best Buy install dept should have an adapter harness.

 

Sounds like he already cut it so he can go either way now.

It uses a very common BT-ISO-DIN. He can get it almost anywhere. I believe Walmart sells it or you can get it off Amazon or eBay probably cheaper.

This is a picture of it. See if it's the fit to your trucks connector you cut off that plugged into the old stereo.

 

Just make sure the adapter has the wires in the right spot. I got my adapter for my 09 at a freightliner and had to use a test light to find two hot wires just to get the stereo to power on. Had to move two wires in the adapter. Funny thing is the constant hot is M.I.A. Going from the ground in the harness to the yellow made the ABS light come on and threw faults up on the dash as long as I was touching the pin. These Cascadia's wiring is goofy as all get out.

 

Yeah buy one specific to your vehicle. This particular one fits 2005 on up Freightliners, Volvos, Kenworths and some Internationals but the color coding and pin count/location might be different. I always make sure to have the schematics. Too much money involved to be guessing. If you want a good looking job use them heat shrink butt connectors.

 

Most use a VW adapter.

 

Metra 70-1784. You may have to move some pins.

 

My friend did the same thing - cut the wires and connected them without any harness adapter. Obviously, he connected them wrong. Now, he is asking me to fix it but all of the wires are the same color and marked only with letters and numbers. I can't find which one is where for this particular model (2014 Cascadia).
Does anyone have any idea how to read them correctly? I need diagram similar to this one that I found for 2005 International