I just purchased a used 2006 limited 4x4 with the V8. The car has the trailer towing package including hitch and 7 pin connector. I need to tow a trailer with electric brakes. Does the X have a built in trailer brake controller or do I need to add one. Does it have a plug wired for a controller if it needs one? I have used the search function and can't find any answers. Please help!