I have an 03, XL. I decided to install one of my sons head units in it. I bought the mounting and wiring kits.
I got it installed, had it working, set the radio stations and clock then I shut the key off for a minute and it will not come back on.
I double checked all the fuses, I tried it with the truck running.
I reinstalled the factory radio and that won't play, but the clock works so the hot from the battery is still good. what am I missing??

 

Recheck all the wire connections. Mostly the signal wire that tells the radio it's time to turn on.

 

Check the power pins on the FACTORY harness plug. My 12v + constant pin got messed up and my radio lost all power. I didn't figure it out until AFTER I replaced it with a new one. Just check your pins and if any are messed up, jump it across the plug..

 

I checked the pins, they seem to be ok. There isn't power upstream of the plug either.
This is the red wire in the head unit harness, purple and black in the truck harness.

 

One more thing I noticed, the wipers do not work on accessory either, only in the on position and while the truck is running.