Burnt 12V Switch
Posted: Sun Sep 11, 2011 6:04 pm
Was making a checklist of things to work on - fairly long list (1980 Tri-Cabin) - and I was testing the forward head vent fan. I had turned on the three vent 12V switches on the main 12V panel.
After a bit - maybe 30 minutes - I smelled smoke! Saw some smoke and a burning smell coming from the 12V panel. I cut the two main battery switches and unscrewed the panel.
While the panel was off - I flipped on first battery number 1 - no smoke. Flipped on battery 2 and sure enough smoke - coming from the switch to the galley fan.
I ended up pulling the switch out - picture below. I knew the galley vent did not work - but it must be one hell of a short somewhere in that circuit to cause this switch to melt! There is evidence of quite a bit of water leaking in the lower part of the galley as the wood is quite rotted - right along where that vent is located under the cupboard.
My question is this though - are the two 12V DC Main swicthes circuit breakers or just big switches??
I was surprised that a switch would melt without a breaker tripping - if in fact they are breakers.
For saftey sake - should individual fuses be put in line that could perhaps stop this from happening? Any ideas appreciated! Thanks, John.
PS - I always make sure these two DC Mains are OFF when I leave...

After a bit - maybe 30 minutes - I smelled smoke! Saw some smoke and a burning smell coming from the 12V panel. I cut the two main battery switches and unscrewed the panel.
While the panel was off - I flipped on first battery number 1 - no smoke. Flipped on battery 2 and sure enough smoke - coming from the switch to the galley fan.
I ended up pulling the switch out - picture below. I knew the galley vent did not work - but it must be one hell of a short somewhere in that circuit to cause this switch to melt! There is evidence of quite a bit of water leaking in the lower part of the galley as the wood is quite rotted - right along where that vent is located under the cupboard.
My question is this though - are the two 12V DC Main swicthes circuit breakers or just big switches??
I was surprised that a switch would melt without a breaker tripping - if in fact they are breakers.
For saftey sake - should individual fuses be put in line that could perhaps stop this from happening? Any ideas appreciated! Thanks, John.
PS - I always make sure these two DC Mains are OFF when I leave...
