Odds of finding an original wiring diagram from Sunline are slim. However if you are looking for the 12 volt running lights and brakes, this diagram can help. The actual trailer DOT light system was industry standard. I'm assuming your system is on a 7 wire plug setup.
Trailer Wiring Diagrams | etrailer.com
Hope this helps.
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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