12 volt issue

[Bslo]

I just got a 2021 Sierra 5th wheel. The first weekend out I had a fuse blow for all the lights in the slides and basement. Replaced it no problem. The following weekend lights didn't work. Checked fuse was blown. Went to replace it and immediately blew. This tells me a short somewhere. I disconnected all the switches and tried to replace a fuse to start to try to figure out. The fuse blew immediately again. Fuse block said I am getting 13.5 volts to that particular spot. Not sure if converter is acting up already or not. Looking for input as to where to start looking. Thanks for any help.

[rracer5]

Originally Posted by Bslo

I just got a 2021 Sierra 5th wheel. The first weekend out I had a fuse blow for all the lights in the slides and basement. Replaced it no problem. The following weekend lights didn't work. Checked fuse was blown. Went to replace it and immediately blew. This tells me a short somewhere. I disconnected all the switches and tried to replace a fuse to start to try to figure out. The fuse blew immediately again. Fuse block said I am getting 13.5 volts to that particular spot. Not sure if converter is acting up already or not. Looking for input as to where to start looking. Thanks for any help.

Sounds like the most likely place to find the short is in the flexible harness under one of the slides that feeds the 12v lights. The first time, you got lucky as the wire most likely made contact again. But, after that, the flexing of the harness as the slide goes in & out finally finished cutting/breaking the wire. It may not be easy to find.