need help

[Edward Mayfield]

I am new to the rv world I have a 1969 prowler 20 foot tow behind trailer and on oct I lost all my a/c lights in the trailer except for the bath room. I have power to all lights  when the lights are off but when I turn a light on then I lose all a/c power to the lights. To me it sounds like a bad braker how ever none have triped, can some one help me or maybe point me in the right direction please. and it just had to happen on my birthday to

[Rich Thomas]

Yes, as John T Nordhoff noted, proper terminology is needed in cases like this. I'm guilty of bad terminology at times even though I was an electrician for many years. I would be guilty of miss spelling big words too if it weren't for spell check LOL. 

[John "T" Nordhoff]

  A LITTLE HOUSEKEEPING AND PROPER TERMINOLOGY ARE IN ORDER, NOTE I suspect an open "NEUTRAL" (White) that's NOT the same as what some call a "Ground" wire. The White Neutrals are insulated live return current carrying conductors while the bare/green Equipment Grounding Conductors are there to ONLY carry Fault Current. If an Equipment Grounding Conductor (bare/green) was open, that would NOT stop a device from working HOWEVER if that were open there wouldn't be a dedicated low impedance FAULT CURRENT RETURN PATH which enables the breaker to trip and de energize the circuit to save a life or prevent a fire. At the main service entrance panel the Neutral is bonded to a Grounding Electrode Conductor (bare No 4 copper) that leads to a Grounding Electrode (say a driven rod) and the Ground Buss and Neutral Buss are bonded together. HOWEVER at a sub panel such as in the RV, the Neutral Buss and Ground Buss are SEPARATE AND ISOLATED from each other.

 LOOK FOR AN OPEN WHITE NEUTRAL not an open bare/green "Ground"

 Hope this helps and doesn't confuse, but after working in the field 40 years hearing the wrong terms is like fingernails on a blackboard to me lol

 John T

[Edward Mayfield]

Thanks John "T" locating all junction boxes now seems like every good place to start

[Rich Thomas]

Yep open ground wire, look for an area that is common to all the failed lights like a J box close to the last light that is working. good luck.

[John "T" Nordhoff]

  Not being there I cant say for sure, but I think Jim is on the right track. Inside the RV's AC Distribution Panel there is a Neutral Buss where all the white wires are attached and an Equipment Ground Buss where all the bare/green Equipment Grounding Conductors are attached. Then throughout the RV there may be junction boxes where wires are spliced/joined often by twist on Wire Nuts. Id be suspecting a loose Wire Nut in a junction or a loose Neutral wire somewhere.

 John T  Retired Electrical Engineer

[Edward Mayfield]

Ground wire now I would never have looked for that thanks will let you know

[jim and penny booher]

good morning Edward, I had a similar problem and it turned out to be a ground wire that had come loose at one of the junction boxes. hope this helps