Hello,

I have an ambulance that is blowing the #10 fuse as soon as the light switch is pulled to its first setting which is parking lamps. #10 fuse is a 20 Amp which runs main light switch, park lamps, license lamp (external lamps), multifunction switch (flash to pass), and BSM.

The automotive shop in which we go to isn't equipped to fix this type of issues to say nicely. So if someone can offer some assistance on how to fix this i would greatly appreciate it!

 

First thing to check is any add-on wiring. Since this is a Ambulance, I bet it has plenty that has been added. I would see if there is one point where they tied into the brown wire for the Ambulance body lights. If there is, disconnect it, and see if the fuse still blows. Another area to look at is any trailer plug wiring in the rear bumper area. That's another place where wiring is added and usually causes problems.