Strange electrical issue, 12v side

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.

JeffPax

Well-known member
Joined
Apr 17, 2013
Posts
100
I have a large 5?er. We live in it half of the year for work all over the country, and have for the last 5 years. A week ago, the two individual lights in the living room slide went dim. (LED?s)
This went on for some time despite fiddling with the switches with no change. Then, on their own, they went bright for a few seconds, then dim for a short while, then off. This process more or less repeated for 2 days, then they stayed off. As a side, it seemed that one light was slaved to the other one.
The same night this started, when we went to bed (which is also a slide), I turned on the reading light to read, which I don?t normally do. I remarked to my wife, who reads all the time, how very bright the LED?s that I had put in the reading lights were. I wanted to show her the difference between these and the original bulbs, and went to where I had stored them to swap it out. I pulled the LED and replaced it with the one incandescent I had found. It didn?t light up. I thought that the filament must have been damaged in storage. I reinstalled the LED, and now it didn?t work! It was extremely dim, barely lit, even worse than the living room bulbs. It had worked perfectly only seconds before. And now my wife?s was barely lit as well (slaved?) Fiddling with the switch on mine a few times, it began to work, as did hers, and I read a little while, shut it off, and went to sleep. Currently, neither light works at all. And after testing the incandescent in another fixture, the filament is fine.
The living room slide lights are the incandescent surface mount, single dome, slide switch variety while bedroom slide has the pivoting/rotating reading light with the rotary switch. All bulbs were replaced with led?s 4 years ago. Being unsure of which circuit these lights were on, I did check the fuses, and all had continuity.
Now this morning, the hot water heater did not fire of while wife was on the shower. I went out, pulled the thermal, plugged back in, and no click from the valve could be heard, but the igniter did trigger. So I unplugged and replugged again. This time the valve clicked open, igniter triggered, and it lit. Also this morn, the outside porch light (also led) was flashing like a fluorescent light with bad ballast. I figure it will quit working entirely very soon. Both porch light and water heater are located passenger side, while original light problem in slides was driver side.
As a side, I replaced the batteries one year ago with AGM's from bass pro, and the converter is 3 years new, progressive dynamics.
 
Classic "Bad Connection" Symptom.. However I will tell you when I had something like that happen on one circuit here in my Rig it was not the connection, it was the wire itself that went bad.

This, however, is rare

If you are not connected to shore power start by cleaning the battery connections, then you are going to have to work your way along the power lines.
 
If the LEDs are on dimmers that would be where I would start.

Check for corrosion on the fuse connections and especially the ground connection.
 
Almost certainly a battery connection issue. The frame ground would be suspect in my book.
Inspect, clean and tighten all connections. Don't forget the converter connections from the battery.
 
Should've said, connected to shore power, no dimmers. Thanks for the replies guys
 
Agreed, the converter will get a look. I hope that's not it, but would be better than having to rewire the stupid thing.
 
I would start simple.  What is your battery voltage with shore power plugged in and not plugged it.  It should be around 13.6 with shore power plugged in.  If battery is no good then don't go any further until that is fixed.
 
Voltage at batteries is 13.2 plugged in.
12.5 unplugged and dropping .01 per second
 
Seems to me since you have multiple issues on multiple circuits you need to look for what is in common with all those circuits, the ground, as previously stated. The converter is one source of 12v, and the batteries are second source. So for the 12v supply to be a problem from two different voltage sources would be a stretch for me, unless they both tie in at one common point, which would be another place to look.  I would disconnect the batteries (positive terminals) and unhook the shore power too before doing any disconnect of the ground though. Make sure the connection is nice and tight and clean to the frame and the lug on the cable too. You could run a temporary ground to the frame from a different spot to the system ground to see if it corrects the problem. Just a thought, I am no RV expert by any means.
 
Nothing good to report. Finally had time to take a better look at this today. Was laid off yesterday, traveling to next job tomorrow, so today was the day. Check the grounds on the slides, they were good. Check the ground on the batteries, good. Went back to the fuse box with the multi meter, two circuits with nothing coming in. Pulled the box to check connections, still no juice there, connections were good. Went to the cold air return chase where all the wiring comes from every direction and meets, to see if there was anything obvious there like a chafed wire/failed crimp connector. Everything looked okay there.
At this point it's above my pay grade. Will pursue it more after spring season is over with and I can get some help or hire someone to come in. Thanks to everyone for the advice. -Jeff
 
Well... I had the mobile RV guy here in Hershey come by, Jim. He found the broken wire in the first place he looked, on the frame rail whee the harness runs through the hole in the frame.
Does one of those smiley faces have egg on it? Geez!
 
Do not feel bad.. I've had jobs I looked at where.. Totally by chance.. I found that the very first thing I saw was the problem.. I mean I just happened to be positioned to look directly at it.. Total chance... I came off looking like a genius but trust me when I say it was 100% LUCK. no skill at all involved.. I just got lucky.
 
Back
Top Bottom