We do not have many truck camper members, but we do have some. I have not seen the truck campers, but have you tried to trace the wiring back from the 5 or 7 wire cable that plugs into the truck? When you said running lights I thought you meant the DOT body, clearance lights. If that is not the case, let us know. Normally there are no fuses in the running, DOT, body lights circuit. They are connected directly to the 7 wire plug to the truck. Since your camper has no brakes on it, they may have used a 5 wire flat plug.
Hope this helps and please report back what you found. This helps other members in the future.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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