I'd been wanting the option of using the FSJ for local light duty towing and started wondering where to mount a brake controller. The few options I considered were (1) on the lower dash just below and to the right of the steering column by driver's right knee, (2) replace the ash tray slot in the dash, or (3) reconfigure the new glove box gauge panel. A brake controller should be within quick arms reach and the display should be visible so these options seemed reasonable. I already had a dash mounted fuel tank selection switch just below and to the right of the steering column replacing one of the cigarette lighters and just didnt like the conflicting real estate to put the controller there. I didn't feel like re-fabricating and rewiring a new glove box panel but i think this could have been the cleanest method. I don't smoke or use the ashtray to keep small things considering the center console can handle storage so started crafting a method to replace the ash tray slot in the dash.
I had an old Reese Pilot controller that got replaced with a nicer controller in my diesel truck. If I don't like the cheaper time based control I can always upgrade to an inertia based controller later. The Reese controller conceptually fit in the ash tray slot with room to spare so an AL plate was fashioned to provide a slip fit. A dab of JB weld locks it in place for now. The dash tabs that used to secure the ash tray sliding mechanism were folded forward to the dash surface plane and the new brake controller mounting plate secures to those tabs. The controller does protrude from the surface a few inches since the slide and side adjust dial need to be accessible. I was thinking about mounting the controller to the ash tray's slide so it could retract flush to the dash surface when not in use but decided to just keep it simple.
The controller needs a 12ga fused +12V (black), 12ga GRND (white), a tap off the cold side of the brake switch (red), and an 12ga output (blue) to the trailer connector. Here is a generic diagram off etrailer website for reference:
I bought a Reese Towpower 85060 Brake Controller installation kit since the FSJ doesnt have a plug and play harness already. It does however at least have a brake switched plug I was able to simply tap into. It's the out of focus plug in the foreground with red and pink wires. The red has constant +12v and the pink is the cold side of the brake switch that is needed for input to the brake controller.
I mounted the trailer connector, a Hopkins multi tow adapter #47185 with both 4 pin flat and 7 pin plugs https://i5.walmartimages.com/asr/a2f...odnBg=ff ffff
, up behind the rear bumper and left some excess wire in a loop for whenever I build my own rear bumper.