12v accessories flicker when tapping power converter. How to bypass?

[K_rex]

19 foot scamp just recently purchased. While doing some work on it and using battery power (not plugged into shore power) for lights and fans noticed some flickering while walking around the trailer. Checked wires under bench to see if anything lose and all all breakers and fuses seem good. Started tapping the converter with my finger and found that is what seems to cause the lights and fans to flicker.

Will pull it out and check for lose connections internally, but if the converter is going bad, how would I go about bypassing it and still have 12v AC and 110V stuff work? Happy to buy a battery charger and charge that way but not sure how to bypass the converter if the problem lies in the unit.

Going out for the first time this weekend and going to be in the 40s, would love to be able to use the furnace and with daylight saving over use the lights.

[Borrego Dave]

That sure sounds like a loose connection to me K. Give all the screws a little more twist and tap the crimp joints also.

[Byron Kinnaman]

Originally Posted by K_rex

19 foot scamp just recently purchased. While doing some work on it and using battery power (not plugged into shore power) for lights and fans noticed some flickering while walking around the trailer. Checked wires under bench to see if anything lose and all all breakers and fuses seem good. Started tapping the converter with my finger and found that is what seems to cause the lights and fans to flicker.

Will pull it out and check for lose connections internally, but if the converter is going bad, how would I go about bypassing it and still have 12v AC and 110V stuff work? Happy to buy a battery charger and charge that way but not sure how to bypass the converter if the problem lies in the unit.

Going out for the first time this weekend and going to be in the 40s, would love to be able to use the furnace and with daylight saving over use the lights.

You can do what I did about 5 years ago, turn off the converter. I haven't missed it a bit. The only time I'm plugged in when the trailer is at home beside my house. Then I connect a battery Minder to the battery to keep it charged up. When traveling the tow keeps the battery charged and when camping I pull out my solar panel about every 4th day.
I wouldn't expect everybody to be totally able to do that, the only battery usage is for couple LED lights and furnace fan. No electric water pump, no television or radio.

[Joe Romas]

My experience with converters when on battery power they are mostly passive.

When you plug into shore power is when they "convert" 120 vac to 12vdc.

So I would start at the battery and check all 12 volt lines to the converter.

If you don't find a problem start looking for problems in the white negative lines.

Joe

[Raspy]

The OP said the trailer was NOT plugged in when the lights were flickering. How can the converter be the problem?

[Byron Kinnaman]

Originally Posted by Raspy

The OP said the trailer was NOT plugged in when the lights were flickering. How can the converter be the problem?

Good catch, good point.
In some trailers if not all, the converter also provides distribution and the fuse block. I think I would look there.

[Darral T.]

The op doesnt say what type of lights are "flickering". I had ALOT of trouble in my Scamp when I first got it BRAND new with the old incandescents flickering horribly. Finally, I went in and applied some "dielectric" grease to the bulb/sockets and firmly twisting the bulbs in and out to help the connection and havent had a problem since. You probably shouldnt experience any with LED's because of the low amperage draw...at least I havent.

Twist your bulbs in and out and see if that instantly stops some of the flickering. Also (BE CAREFUL THEY'RE NOT HOT) take one or two out and see if it's "chalky" looking caused by oxidation. THAT is what was wrong with mine and the dielectric grease fixed it. I havent had any flicker in YEARS now.

Just a suggestion...wont hurt to try it (as long as the bulb's not hot! )

[Joe Romas]

Darrall.

They also have fan speed problems.

[Darral T.]

Hmmm...you're right (reread it...thanks Joe). I've just never heard of a fan "flickering"? Bad ground?

Originally Posted by Joe Romas

Darrall.

They also have fan speed problems.

[Wayne Collins]

Electical, or Electronic devices can be a royal pain to diagnose for intermitent connections. One trick is to feel the temperatures of the wires near any terminals or connectors. Warm wires are a result of high resistance. Of course you need to have all the 12 v devices on for a while so current is flowing.
Sadly, getting at the converter box can be a challenge when it is back under the bed.

[K_rex]

To answer some questions and give an update.

Pulled cover off everything seemed tight but retightened just to double check. All 12volt lights seemed ok. Then I was just back in Scamp a while later with battery unplugged but 110 hooked up and (12 volt) lights still flickering. In fact when I turned on to many lights (12 volts) they all dimmed or just shut off completely. The 110volt flourecent light has no problems. Taping converter with my foot also made lights flicker on and off or come on when they were off.

Edit: Some of the lights flicking on and off are LEDs.

This is getting frustrating.

[Borrego Dave]

Originally Posted by K_rex

To answer some questions and give an update.
Pulled cover off everything seemed tight but retightened just to double check. All 12volt lights seemed ok. Then I was just back in Scamp a while later with battery unplugged but 110 hooked up and (12 volt) lights still flickering. In fact when I turned on to many lights (12 volts) they all dimmed or just shut off completely. The 110volt flourecent light has no problems. Taping converter with my foot also made lights flicker on and off or come on when they were off.
Edit: Some of the lights flicking on and off are LEDs.
This is getting frustrating.

Lets see if I have this right K. You've tightened all the connections and you say they seemed OK. Does that mean you checked them and they are working OK now with no flickering on 12Vs only without the converter being plugged into shore power? Next you said you were on shore power with the battery disconnected and 12V equipment still had problems. Am I correct so far, the 12V system on battery alone is OK but is flakey when plugged in? Being on shore power, your converter should easily power up all 12V systems at the same time. If it's OK on battery but not when plugged in...it's in the converter somewhere. Loose connection you haven't seen yet, an iffy solder joint or even a cracked ckt board. Might try touching things in the converter with a non conducting item to isolate it instead of tapping on the frame .

[K_rex]

It's happening on both shore and battery power but only to the 12 volt appliances. Is there a connection behind the power converter I might not be seeing? I've jiggled connections and wires all over the Scamp and only seems to happen when I tap the converter itself. Is there a way to bypass the converter temporarily to just have 12 volt appliances only run off battery as I won't have shore power this weekend anyway in case it's something to do with motherboard that is not fixable? Are there detailed instructions instructions on how to replace the converter?

Also thanks in advance for the advice.

[Joe Romas]

K_Rex

At this point we need more information on (a) what year trailer and (b) what brand and model converter you have.

While most here own trailers, this forum is specific to molded fiberglass trailers but there are brands with different converters so we (me) might not know what converter you have.
So far we know you have a 19' Scamp.

Joe

[Darral T.]

If it's doing it with or WITHOUT the converter, they still have a "loose" connection somewhere. When they tap it if flickers...still doesnt mean it's in the converter. This is going to be very tricky but at this point. I'm beginning to believe they need the Scamp's wiring diagram (Scamp can furnish this) and start "tracing" wires..... COULD be a "wire nut"!! Scamp uses them religiously and they HAVE been known to cause problems!!

So...K-Rex, at this point, I'd start looking for "wire-nuts" and resetting or replacing them.

[k0wtz]

I am thinking he needs to start at the front of the trailer under the seats and while the 12v is on start to move wires around working his way back. Yes at each wire nut too. it sounds like the main wire which I think is red and black is where his problem is. sometimes wiggling wires will disclose such problems!

I would also go back to that converter and retighten every screw where stuff goes in and comes out.

If this is a new rig then scamp should stand behind it I wouldn't wait too long to file with them. if not found it needs an rv shop to look at it!

bob

[Darral T.]

Personally..I dont think it's new. New owners come in here "bouncing off the walls" with joy.

Sounds like they've already screwed on the converter. But if it ONLY does it tapping on the converter, I guess we all agree, there COULD be a loose connection from inside since the battery runs to the converter to be charged while on "shore" power.

I wouldnt advise K-Rex HOW to do it, but I do think maybe bypassing the converter at this point is the thing to do. If they still "flicker" on battery-only, that only leaves ONE option- loose connection(s).

Originally Posted by k0wtz

I am thinking he needs to start at the front of the trailer under the seats and while the 12v is on start to move wires around working his way back. Yes at each wire nut too. it sounds like the main wire which I think is red and black is where his problem is. sometimes wiggling wires will disclose such problems!

I would also go back to that converter and retighten every screw where stuff goes in and comes out.

If this is a new rig then scamp should stand behind it I wouldn't wait too long to file with them. if not found it needs an rv shop to look at it!

bob

[K_rex]

Hi all I have a 2006 19 foot scamp with the factory American power converter. Front bunks, side shower and the converter is located under the fridge. As of just 20 minutes ago went into the trailer before work (still on shore power and no battery connected) and turned on each 12v light one by one and nothing but the faintest little light coming from any of them. Give the converter a tap and lights would go to full brightness for a split second.

I have shaken some wires under the front bench where the battery power comes in and the rear dinette/bench and that seems to have no affect. But tapping the converter definitely does.

Also, I'm now fairly certain the battery wasn't charging on shore power. Took the battery to get tested last night after being hooked and on shore power and it was low. Have the battery on its own charger now.

Can any let me know where on the frame the ground might be connected? I've looked and can't seem to find it.

Is there connection behind the power converter that I can't see that I should be looking at?

[Joe Romas]

Maybe you can find more support with your problem here. But it sure sounds like a connection problem
Couldn't find out much on American Power converts.
https://www.scampowners.com/forum

Joe

[K_rex]

Epiloge: Resolution (a bit long)

Came home and looked under the trailer for grounds. Saw one under the converter area with no wires attached and two grounds on the frame next to the wheels with red wires coming from the wheels the attached to the frame for the trailer brakes. Thought maybe that's how the ground worked on this trailer but made a mental note.

Tried pulling out converter. It was attached to so many wires I quickly became overwhelmed. Noticed that when touching the side closest to the motherboard the lights would go on. So got nervous the board was shot.

Did some more poking around with very little space and noticed two white wires and a thick gage copper wire coming from the back of the converter. They ran into mess of wires and wire nuts in the back in a very hard spot to get to and i began tapping all to see if anything happened. That's when I noticed the copper wire was rather long and just simply wrapped around the gas line for the fridge and that was it. So remembering the open ground crimp on the frame I gave it a whirl and drilled a hole in the floor and ran it through the crimp on the frame and plugged the shore power on and then nothing would turn on. I was dismayed and sat there for about 20 min about to give up when I noticed one of the 110 breakers must have been shut off when I was digging around turned on and viola everything works!

For the love of me I can't figure out why the ground was wrapped around the gas line. Seems dangerous.

Thanks all for the guidance!

One last question, is it normal for trailer brakes to be grounded to the frame on each side?