12 volts shutoff then come back on???

[dnrtheil]

I stayed up till 2am searching for my particular problem and could not find anything on it. Everything I found even related the owner had the 12v lights turn off and not come back on until they searched and found a bad switch or fuse. We have owner our A/S for four weeks now, ever since the interior lights have periodically changed from bright to dim and bright isn’t really all that bright even less so running off the battery. Last night I was in the A/S (Felix) doing some painting, had almost all of the 12v lights on and a 120v space heater not to mention my iPod. The lights were doing their normal bright/dim dance, then all of a sudden all of the lights shutoff for a few seconds then came back on, didn’t seam to go from bright to dim any more just on or off. Heater was still working fine. Lights would be on for a few minutes then off for a few seconds, even after switching to the battery. Since bringing Felix home I have not had a chance to look for any fuses or taken a real close look at the electrical, up till this point everything electrical I have needed to use has worked; only things that need fixing have been worked on. All most al of the threads I read last night mentioned getting rid of the old “univolt” in favor of a new modern converter. So my question is this, does it sound like the univolt is the problem? Should I just get a new one and start from there or should I look closer at the fuses and switches before switching to a new converter? Also, when the lights go out I do not have enough time to check if the univolt is still humming or not, did not want to walk through Felix while dark and risk kicking over the can of paint.

P.S. I am not allowed to refer to our Airstream as a trailer, a camper or thing in the driveway, only Felix or Airstream.

Thanks - Derek

[overlander63]

I think you have more than one problem with the ioghts. You probably have a weak Univolt, with either bad connections or sself resetting circuit breakers. Do the lights go off when not all lights are on? Our Overlander has a 20 amp self resetting breaker on the lighting circuit, if I turn on all the lights, after about 5 minutes the lights will cut off for maybe a minute before coming back on.

[Aerowood]

If it is all the 12 volt lights I would look at the electrical connection that supports all of the lights. Almost sounds like a dirty or bad common ground.

[Excella CM]

The symptoms you describe are most likely due to a bad connection, and as previously noted, may be due to a bad ground. Bad connections are high resistence connections, and as a result generate heat. This gives us a way to find them. If you have laser thermometer, just point and click, otherwise, poke around with your finger after the system has been malfunctioning a while. You will find the culprit by the warmth (or hot-th, so be careful )

[dnrtheil]

Looked a bit closer at the electrical system today. I have resetting circuit breakers, all of which have rusty connections, did notice the ground wire was also rusty. Looks like I'll start cleaning all of the connections and see where that gets me.
Thanks - D

[john hd]

those self resetting circuit breakers do have a definate useful life.

they do wear out. if you cannot find a problem, try replacing the breaker with a fuse. once you have verified there is not a short circuit you can replace the breaker.

they can be found at most auto parts stores, napa comes to mind. a well stocked RV dealer may have them as well.

oddly enough, they are exactly the same breakers harley davidson used in the 70's through the 90's.

john

[lewster]

Read this thread Another 'NEAR' Disaster.... about a situation I found in a big MoHo a few days ago. It points to the problems that are caused by loose connections.

It could have just as easily been the ground that was the problem in this case. Excella CM's use of a laser thermometer is a good one, as you can get into very thight areas that your hand might not, just for troubleshooting.

[TomW]

Originally Posted by john hd

those self resetting circuit breakers do have a definate useful life.

they do wear out.

I had a problem just like you (and Terry) described. It ended up being a bad, self-resetting circuit breaker.

See this thread for pictures & more detail.

Tom

[HowieE]

With all the lights on for a period of time you most likely have a bad circuit braker. Find the braker panel, most likely under the front window, then turn all the lights on and wait about 5 mins. Then touch each of the brakers and see if one is warm. If so that is the one that will eventually open. Replace it and test again.

As for the lights dimming I would put a volt meter across the output side of the convertor and test to see if it is cycling while under load. If the voltage is dropping while a full load is on the convertor circuit braker may be opening. Reduce the total load, turn half the lights off, and test again. If the lights still dim consider repairing or replacing the convertor.

[dnrtheil]

In my '64 Tradewind all of the elctrical items are in the back left corner. I removed the box holding the resetting circuit breakers and city/battery switches and also the univolt. No real ground wire to speak of, shore power come into the main breaker box, the goes to the univolt with two 120v three wire cords then to the resetting breaker/switch box. No ground from univolt to trailer frame or body that I saw clearly. Have not really had time to trace were all of the wires are going. Had to get the interior walls painted before I ran out of day light.

D