thanks SS and for MC it is the "total intergrated power module yada yada yada..... "
what i do know is that it is on the drivers side under the hood on area of the fender. it replaced a bunch of relays and fuses on the 06 to present. the problem is that should you have a short in your trailer wiring it will trip and you lose some of your trailer lights, everyone seems to be differnet on which lights are lost, i lost my running lights only. only the dealer can reset it with the star scan tool and it can only but reset a handful of time before you have to buy((around $600-800)) a new one. the reflash increases in amp trip to 20amps from 10 amps so if you do have a short it hopefully won't trip. unfourtunly there is no short in my trail but some moisture after it had rained that caused the trip.
there are some threads on building a fuse box for this to protect the tipm yada yada yada... ... be safe.....