Blown Fuse...

BEPPEQ

Cadet
Joined
Jun 23, 2008
Messages
6
Hi Everyone,

Have a problem with my new trailer.

My 10amp fuse keeps on blowing. When I plug in my trailer after a new fuse, it works for a while and them without doing anything the fuse seems to blow. I've checked all the wires and the only thing I can find odd was a burnt out light bulb.

Could this cause the blown fuse or is it a short? And if it was a short, would it not blow as soon as I turned on my truck and send power through the wires?

Thanks everyone, any advice would be great!

BeppeQ
 

tashasdaddy

Honorary Moderator Emeritus
Joined
Nov 11, 2005
Messages
51,019
Re: Blown Fuse...

how many bulbs do you have on the trailer that burn at the same time. count them and add up the load.
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,771
Re: Blown Fuse...

Fuses blow for two reasons: 1) a short circuit or 2) too much current. Too much current is caused by too many bulbs. Look at it this way -- If you had a 3 amp fuse in a circuit that had four bulbs each of which drew 1 amp of current, that 3 amp fuse blow every time. It its the tail light fuse that blows, your new trailer likely has 9 lights on that circuit if the trailer is over 80 inches wide and six if its under 80 inches. at 1/2 - 3/4 amp each you can easily exceed the 10A fuse rating.
 

BEPPEQ

Cadet
Joined
Jun 23, 2008
Messages
6
Re: Blown Fuse...

Thanks for the reply guys.

My trailer has 6 side lights, 2 tail lights and 3 small lights under the back of the trailer. (hope that makes sense)

I understand the idea re:fuse and the amps but my truck has one of those modulite adapters so I am assuming the 10A fuse is for that.

Either way......

I spent a couple hours taking a look at the wiring but couldn't see anything "visible" but when I put the wires back into the trailer frame it now works fine.

Can't explain it but my best guess would be that something was touching the frame and when i pulled on the wires it's not touching anymore. I know, I know, a temp fix but at least it's working now.

Thanks again!

BeppeQ
 

fdmsiv

Petty Officer 1st Class
Joined
Mar 2, 2008
Messages
283
Re: Blown Fuse...

I had a surface mounted side light with a positive wire and plate/stud made contact with the trailer for a ground. The side light was the culprit, I think it was a wiess wedge shape light. Anyway, the metal ground plate was pinching the pos. wire and was blowing the fuse. Took me a long and frustrating afternoon trying to figure out what was going on. In the end I had to tape the wire down and put a spacer in the light before remounting. Total PITA
 
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