hatchetman wrote:
Found a red wire behind a white-like colored plate marked "electric brake". This I take is the wire for the trailer brake, not for the stoplight/brake pedal wire of the brake controller.
That's the wire I couldn't find

Red with white tracer is the source for the power line that goes back. It should have constant power and a fuse in position 10 under the hood in the power box.
Reguarding your brake wire. Do you have the factory two package or the EVIC? if not you'll have to add the "complimentry" harness to the rear.
Here's a very complete write up on towing wiring on Liberties
http://www.jeepkj.com/forums/viewtopic.php?t=1691