Troubleshooting Marker Light That's Causing Fuse on Tow Vehicle to Blow

Updated 04/02/2021 | Published 03/30/2021

Question:

I bought this light and it is very similar just slightly longer than the old one but the screw holes lined up to the old one that was on my bass boat trailer. HOWEVER, I have hooked it up twice now and it has blown my 20 amp fuse in my truck both times. Why is this happening ? Is it too much load for it ? If so what is a viable replacement for this? My old light was about 4 3/4 inches long

asked by: Jeff M

Expert Reply:

Since you're replacing an existing marker light instead of adding additional lighting, it's extremely unlikely that you're drawing too much power on the running lamp circuit. Instead, I'd look for a short circuit somewhere in the running light circuit. Look for loose wire connections, pinched wires or wires with cracked or worn insulation that would allow the copper wire to short out on the trailer frame.

expert reply by: Mike L