Intermittent Fuse blowing

[C7XR7]

• I recently purchased a lightly used '03 keystone Challenger 5th wheel. 31RLB
• I am pulling it with an '06 F250 SD.
• On our little shake down trip this past weekend I was alerted by a passerby that my brake lights were not working on the trailer. Turn signals also not working.
• All trailer lights checked out working prior to departing on the trip.
• After some diagnosis we determined that fuse #9 located under the hood of the F250 had blown. A 20A fuse for the towed units brake lights and turn signals.
• We replaced the fuse and all checked out as working.
• Somewhere on the road back home the fuse blew again.
• Any suggestions on the proper way to proceed in diagnosing where this electrical short may be occurring?
• Anyone ever report having this issue before?
  Thanks!

[raytronx]

I had a similar issue with my 2011 Cougar, except it was the running lights failing and popping fuse in truck. Turned out to be a pinched wire the only acted up when hitched up.

Here is a link to my blog detailing what I found, may help a little.

http://www.loveyourrv.com/finally-i-...unning-lights/

Good luck, they can be tricky to find when they are intermittent.

Ray

[Ken / Claudia]

Sounds like a wire is grounding out SOMEWHERE. Good luck finding it, it maybe something for a shop or someone with the right tools.

[SAABDOCTOR]

Ok roll up your sleeves put some adult beverages on ice for LATER!!!!!! If you can get a proper amperage circut breaker that will save some $$ on fuzes. put the breaker in and since this only happenes with the camper plugged in the tv is good. start at the plug form the camper. plug it in and start twisting and plling on it. if ok go to the junction box in the goose next take the cover off and check there.good go the the back lights. remove the bulbs look at the filiments and the contacts at the base of the bulbs. I have seen the contacts melt and short out to ground and the filliments touch the case and short when going over bumps.if good pull the lights and check the wiring. if all shows good the you need to start fallowing the harness through the camper that will take some time. work slowly and carefully and you will find it. all campers are different. most likly you find a chaffed wire where the harness makes a tight turn or can rub on a moving part. when your done consume the chilled treat! wish you the best. let us know what you find. there is no easy answer to this. all the best

[C7XR7]

Thanks, I have confidence I can trace this down eventually. I completely rewired a '67 Mercury Cougar XR7 at one point in my life, a true challenge. I was hoping this might have been an issue that was common to others with this type trailer and been able to narrow the search down but we'll go with the old standard inch at a time method.

Beverages are on ice!

Originally Posted by SAABDOCTOR

Ok roll up your sleeves put some adult beverages on ice for LATER!!!!!! If you can get a proper amperage circut breaker that will save some $$ on fuzes. put the breaker in and since this only happenes with the camper plugged in the tv is good. start at the plug form the camper. plug it in and start twisting and plling on it. if ok go to the junction box in the goose next take the cover off and check there.good go the the back lights. remove the bulbs look at the filiments and the contacts at the base of the bulbs. I have seen the contacts melt and short out to ground and the filliments touch the case and short when going over bumps.if good pull the lights and check the wiring. if all shows good the you need to start fallowing the harness through the camper that will take some time. work slowly and carefully and you will find it. all campers are different. most likly you find a chaffed wire where the harness makes a tight turn or can rub on a moving part. when your done consume the chilled treat! wish you the best. let us know what you find. there is no easy answer to this. all the best

[Ken / Claudia]

I guess you will be able to figure out where and how it is shorting. Post what you find and how it gets fixed.