Electrical Quandry

[ParkCountry]

I am in the process of charging my batteries, but I wanted to get a head start prepping it for a trip this weekend. So, I plugged the trailer into my shore power (with no batteries installed). Initially, all electrical items worked. Then the next thing I know, there is NO electrical power. I checked the breaker enclosures in my garage and in the trailer and everything is okay. The strange thing is, the only apparent electrical item that seems to be working is the Microwave display. I just don't get it. I haven't been doing anything different than I have for the past 14 years. Does anyone have any ideas? Thanks in advance!

[ParkCountry]

Thanks, all, for the feedback. Jeff, thanks for the diagram. As they say, A picture is worth a thousand words.

[jeffk14]

MEXICOWANDERER wrote:
Is there a truly off-the-wall-chance that the converter feeds the batteries then has a separate line to the fuse distribution? i.e. Disconnected battery cables, separation of converter and feeder line to fuses? Until a power-loop interconnect failed?

Too many of these types of posts ask for help but the poster neglects to say...

a) Whether they have a meter or test light

b) If they are knowledgeable about how to use either one

"Gee, my back hurts. Can you give me explicit instructions to make it not hurt?"

Some investment in time, effort and money is needed by a rig owner going into these diagnostics or I get the impression that an individual believes in miracles...or magic...

I swiped this pic off the web but typically, the converter supplies the 12V fuse panel and also keeps the battery topped off when connected to shore power. The absence of a battery should make no difference with shore power connected, unless he tries to operate the slide (huge current draw) in which case the converter would probably not be able to handle the load by itself.

[jeffk14]

2oldman wrote:

ParkCountry wrote:
I plugged the trailer into my shore power (with no batteries installed). Initially, all electrical items worked. Then the next thing I know, there is NO electrical power.

Plugging in sans batteries is a normal thing for you?

It is for me. It won't hurt a thing on most modern(ish) RV's, provided you don't let that dangling positive battery lead short to ground. Even then, the fuse should take care of it.

The manual for my trailer even states that no battery is needed when on shore power. You just won't have backup lights, refer or gas hot water in the event of shore power interruption. More importantly, you also will not have any breakaway brakes when towing.

[MEXICOWANDERER]

Is there a truly off-the-wall-chance that the converter feeds the batteries then has a separate line to the fuse distribution? i.e. Disconnected battery cables, separation of converter and feeder line to fuses? Until a power-loop interconnect failed?

Too many of these types of posts ask for help but the poster neglects to say...

a) Whether they have a meter or test light

b) If they are knowledgeable about how to use either one

"Gee, my back hurts. Can you give me explicit instructions to make it not hurt?"

Some investment in time, effort and money is needed by a rig owner going into these diagnostics or I get the impression that an individual believes in miracles...or magic...

[2oldman]

ParkCountry wrote:
I plugged the trailer into my shore power (with no batteries installed). Initially, all electrical items worked. Then the next thing I know, there is NO electrical power.

Plugging in sans batteries is a normal thing for you?

[BFL13]

GFCI? Washing the RV and the outside receptacle got wet, popping the GFCI for all the receptacles, including for the converter?

[Matt_Colie]

Park,

Think about what does and does not work.

The microwave is line powered. So you have shore power.

I bet everything that does not work (lights, fan, water pump and reefer) are all powered by the house 12V bank. Without a battery to handle the peaks, you may have just killed the converter/charger. Check that for output.
If there is, look for a fuse.
If there is not, first try shutting it down and restarting it.
When that doesn't work, go get a new and better one.

Matt