Can we get into questions about the trailer wiring here? Our '99 fleetwood 22' 5th wheel works fine with the 110vac coming into the trailer and works fine with the 12vdc coming into the trailer from the tow vehicle9f-150.
The new, large 12 volt deep cycle battery in the trailer will not, by itself,
power the trailer lights or pumps etc. I see on a generic schematic of the
wiring of the trailer that there is a 40 amp breaker between the trailer's
battery and the fuses for the various 12volt circuits. this would seem to be a likely culprit except that the 12volts from the truck also looks like it goes through this same 40 amp breaker too. If the breaker was stopping
the 12volts from the trailer's battery, wouldn't it also stop the 12volts
from the truck? I have not even found this 40 amp breaker yet. Maybe
there is a way to look at the specific wiring and location of components
for this trailer on line? Any help is appreciated, just dont tell me to take it to the dealer, that is not in the budget! dd

 

We need more info: What "lights" are you talking about? Internal or external?

I doubt if the 40Amp breaker is used for both inputs.... I'd be looking for a 2nd 40 amp breaker OR 40 amp in-line fuse or 2.

It's time to break out the voltmeter or use a 12v test light to run down what is getting voltage and what isn't. I'd start in the area of the battery compartment and start tracing your wiring from it, testing for 12v along the way. DO NOT FORGET THE GROUND WIRES! They are just as important as the hot ones. This is where a ohmmeter comes in handy. You HAVE TO have good grounds!!!

 

Thanks for the reply, Bud. Like the title says, IN THE TRAILER. The exterior lights for stop and turn etc are good. The porch light and everything inside including control power to the fridge are only good with 110vac from the power cord to a "land line" or when the 7 prong plug is into the towing vehicle. Sounds like I am looking for a good size fuse or breaker that is exclusively for the trailer's battery. It must be out of site.... under
the frame or hidden behind a panel that is not normally accessed. right? Yes, I hear you
about the grounds, I will make sure to check that too. Thanks dd

 

Start by tracing the red lead from your battery. By code the breaker is within 18" of the battery. Do not get caught up in wiring diagrams. Find the breaker and test the side from the battery and then on the othe side of the breaker.

Steve

 

Sounds like the battery is having some kind of problem...

When you're plugged in all of your lights still run on 12vdc, only they're running off of the 120vac -> 12vdc transformer instead of the battery itself.

 

It's possible that back in '99 they had 2 sets of lights in his trailer. Some on 12v, some were 115AC. My old Prowler was that way.

 

You will have a metal junction box on the underside of your pin box. Pull the cover and check there. I did not catch this was a fiver on my first read. Fleetwood sometimes locates things in strange places, so you may find your breakers there. I have been down this road with other models more than one time and often is it simply a loose wire in the junction box.

I can't remember on this model. Normally your seven pin power junctures there to the house, but the battery most often has its own feed through or under the body of your camper. Its difficult for me to be specific, but your problem is normally not complex. I'm betting it will be in the junction box or close to the battery.

Steve

 

I noticed you said "the NEW battery" in the trailer. Something I've seen happen more than once when changing batteries is a line (wire) gets dropped behind the battery box and is overlooked when hooking up a new battery.

Gets a little worse when changing 2 batteries. Battery enclosure is usually pretty cramped to begin with.

 

Happens more often than could possibly be imagined. Much worse with fifth wheels because the batteries are often harder to see.

Steve

 

You might want to look around the battery compartment, on the compartment wall or even underneath on the frame near the wireing harness's for a ShortStop Mini Breaker. Some are manual reset and some are automatic reset. They can be most any amperage as mine are 30 amp. I had automatics and had to replace them this summer. They are rather small but I am seeing this on many RV's. They do wear out, just like any electrical breaker.

You might want to look at this link just to get a visual on what I am talking about.

Shortstop Mini Breakers - Circuit Breakers - Power

 

Good to offer a link. That is exactly what I was referring to. Nearly all the manufacturers are using auto resets for the slides, in order to undersize the wiring to the motors and save money. That makes the slides start and stop several times on the way in and sometimes on the way out.

Steve

 

Thanks to all who jumped in to help. The problrm is not located yet, but
we have some excellent information to work with now. I didn't want to
complicate the original post with too much information but the 99
Fleetwood 22' 5th wheel is now back home in Colorado. I am in San Diego.
The fleetwood is my son's and he is a good policeman and athelete, but
not yet a certified shade tree mechanic. With your help and me helping
him over the phone, I think we can fix this. I will repost with results. dd

 

this exact thing happened about 2 months ago on a dry camping trip with my brother-in-law and sister. They keep their trailer plugged in at home and all power worked fine, hooked up to truck everything worked fine. We got out in the woods and my sister has to go everything is working frig, pump and lights. We unhook the trailer and proceed to set up camp. Sister goes in the trailer and no power, nothing worked. We looked everywhere followed every wire and check every fuse. Got the generator out and started it up and everything working again, range that generator for 3 days straight.
When we got home, grandpa looked at the one thing we didn't check, the wires at the battery terminals. Turns out the wires were old (2001) and a little corroded. So, we cut off the ends of the ground wires cleaned it all up with baking soda solution put new terminal ends on and presto everything works again without shore power or being hooked up to the tow vehicle. The batteries weren't getting a good ground through the terminal connectors and the wires but got grounded through the tow vehicle or shore power connection when they were connected.

 

I my 96 Cheatau had that problem. As stated earler I followed the red wire off the battery to the side of the frame of the trailer. Replaced the small little black box. That fuse sits exposed to the elements and was rusted threw. Cost me 10 mins and less than 5 bucks.