I would check the service manual electrical wiring harness for where that wire comes from and when it is 'hot' for a few important reasons. These cars are not your basic hot wire system harnesses any more, they go through modules and are designed for specific current draws for that designed circuit. Tapping into these may cause problems after an install depending on how much you 'load' onto that 'hot' wire you find. Just an FYI, as you know any accessory SHOULD be routed to a fuse center capable of handling the systems added (as written in your install manuals associated with what your adding). A friend up the street from me took his accessory 'bundle' on his 2011 2500 (finding a hot wire under the dash) and burned out his BCM because he overloaded the circuit that had that hot wire. Seeing as he was only a 'shade tree installer/repairman', he finally took the truck to the dealership and 1800 bucks later was back on the road. FYI...


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