12v 'smoke' missing

[motoman]

Get a roll of wire and tie it down to ground on one end. Use the VOM and check between it and the white ground wire for resistance. Should be no more than 5 Ohms, 10 at the outside if your roll is 50'. Wiggle the suspect wire while you check, and see if the resistance changes.
You MAY have a "bad" ground wire, and may need to see if you can find a way to run a "new" wire. Sometimes a fishtape will allow you to push up through the wall so you can pull a wire on back.

Looks to be only option, if at all possible, least as far as runnin' a new wire.
I did go back up both wires and cut a 'nick' in them.....no change.....could only hope though. Popped lense off another lite elswhere in trailer, removed bulb, turned on and had 13.21v. Must be voltage that inverter floats at like Schming stated. Back to living/dining area .....12.34v at the wires of the 'problem lite', and hooked to new lite, still drops to under 2v when lite is switched on. As you've said, could drop down another lite, run a length of wire from its positive to 'ailing' wires positve, then switch it to ground on both. Least that would tell me which wire is missing 'smoke', correct?

[DiverRay]

Start with the ground wire. Get a 25' roll of #14 wire, connect one side to the ground and the other side to the ground of the new light. Connect the 12 in the wall to the new light, turn on switch. If it works, you have a bad ground. If not, you have a bad 12V Positive.
Test #2. Same roll of wire, only now from the 12V. side to new light. Ground to the old ground wire in the wall. If it lights, 12V wire/switch is bad. If not, BOTH wires in the wall are bad!
Test #3. If it lights on #2, connect light as normal in wall, and Jumper a wire across the switch to bypass it. Light works, switch is bad, light fails, wires in wall bad.
Hope this helps! Good luck Brant!

[BA80]

Correct me if I'm wrong but why couldn't the existing wire be used to pull a new wire into place if that was necessary? Unless it was completely broken.

[Schming]

Correct me if I'm wrong but why couldn't the existing wire be used to pull a new wire into place if that was necessary? Unless it was completely broken.

You might get lucky but the wires in my camper are run through cable ties which are fastened so they don't move around while transporting.

[BA80]

So, you've had to remove the paneling to do repairs?

[motoman]

So, you've had to remove the paneling to do repairs?

You definitely would.....and that'ed be like doing a restoration.......they're all wired prior to inards being installed with I imagine 'drop' locations of ending wires. Even the wiring for lites attached to bottom of cabinets over sink/counter as well as lite under cabinets that are above the couch area are hiding between two sections of cabinet base and not exposed.


Thanks Ray.........that'll be my next 'attack', for nothing better than to at least know whether ground or positive isn't carrying the load. Can easily do that with 5ft. of wire, dropping the over-sink lite and 'jumping' off its wires.

[Schming]

Greg, I got lucky when I had to replace a faulty converter in my camper as the kick panel, for the slide out dinette, was easily removed (6 screws) for access. It would take some extreme care to remove the paneling, cabinets etc. for access, as most campers are stapled together, but it can be done.

Brant, have you checked your grounds ?

There is a heavier white wire,that fastens to the trailer frame, near the pigtail that plugs into your tow vehicle and a 4 or 6 gauge solid bare copper wire from your electrical panel/converter area that runs to the trailer frame also. These two, if not in great condition, can cause all kind of havoc, just like on our bikes.
The panel/converter ground, on my trailer, is exposed to the elements and was completely corroded on account of the weather and the dissimilar metals.

[rdmcguy]

Make it easy..

Hey Brant
While it's always preferred to have things as they were as new ,
Instead of Dissasembling your entire interior,
Why not just get some wire mold and run new wires...
Granted it might not be the tidiest looking but it isn't as if anyone besides you will notice...
If it bothers them ...turn off the lights and no one will see anything..
Just a thought!!!

[motoman]

Greg, I got lucky when I had to replace a faulty converter in my camper as the kick panel, for the slide out dinette, was easily removed (6 screws) for access. It would take some extreme care to remove the paneling, cabinets etc. for access, as most campers are stapled together, but it can be done.

Brant, have you checked your grounds ?

There is a heavier white wire,that fastens to the trailer frame, near the pigtail that plugs into your tow vehicle and a 4 or 6 gauge solid bare copper wire from your electrical panel/converter area that runs to the trailer frame also. These two, if not in great condition, can cause all kind of havoc, just like on our bikes.
The panel/converter ground, on my trailer, is exposed to the elements and was completely corroded on account of the weather and the dissimilar metals.

That heavier white wire is attached to center grounding of the 12v fuse panel. Everthing else 12v works, so that central grounding is good.

[XJOK2PLAY]

Brant,
The problem you're describing is a contact/connection problem.
I work these kinds of service calls a lot.
Voltage is present and perfect... until the load is applied.
Too much resistance occurs at the bad point, voltage vanishes.

Now... finding where the bad connection is... is another thing.

May be where they did a bad crimp at a connector... could be from a bad connection in the circuit that's burned.

A lot of times in houses, the problem is either at the last good working point where it leaves out to go to the next one that isn't working, or at the one that isn't working.

Some guys overlook checking at the last light(or switch) in the circuit that IS working...

Sometimes the challenge is figuring out how the circuit is wired, since most of it's invisible and covered up. Get that part, then go through all the connections.
Figure out if the connection problem is on the + or the - side...

I do this every day for my living. It ain't fun, I know.
Hope this helps ya figure it out.
Bob

[motoman]

Brant,
The problem you're describing is a contact/connection problem.
I work these kinds of service calls a lot.
Voltage is present and perfect... until the load is applied.
Too much resistance occurs at the bad point, voltage vanishes.

Now... finding where the bad connection is... is another thing.

May be where they did a bad crimp at a connector... could be from a bad connection in the circuit that's burned.

A lot of times in houses, the problem is either at the last good working point where it leaves out to go to the next one that isn't working, or at the one that isn't working.

Some guys overlook checking at the last light(or switch) in the circuit that IS working...

Sometimes the challenge is figuring out how the circuit is wired, since most of it's invisible and covered up. Get that part, then go through all the connections.
Figure out if the connection problem is on the + or the - side...

I do this every day for my living. It ain't fun, I know.
Hope this helps ya figure it out.
Bob

Well, using a jumper wire going from lite over sink/counter to new lites wires , first to ground then thru positive, surprisingly the positive is the culprit not able to carry the 'all important smoke'. That bites, cause with rdmcguys idea could of nicely covered a 2ft. wire straight shot to the AC inside housing mounting screws for grounding. Having three, blade fused 15A LIGHTING circuits and some 16 seperate lites inside and out, definitely more than one lite on a circuit. ALL other lites and 12v socket sources work fine.
Thanks for the ecouragement Bob!............Thinkin' some 'riding therapy', since I haven't thrown a leg over either bike for over a month.

[motoman]

Thanks ALL for your input! What was throwing me for a curve was the fact the lite wires showed 12+ volts across them. IIRC, Ray's(Diver Ray) suggestion of voltage check with lite attached and in ON position.......and then process of elimination as to whether positive or negative was culprit from known good power source was key to isolating which wire wasn't easily 'carrying' the 'all important smoke'.

Original manuals, which give specs., pics and removal/installation of ALL appliances, etc. with unit showed a top-view of 12v wiring layout(including appliance/ furniture layout. The problem lite is first in a 5lite series of that circuit. Previously mis-spoke as there is 4 not three seperatly fused lighting circuits originating from fuse panel. From manuals 12v wire pics., that circuits power source wires run in ceiling right past the AC unit. My guess would be one may be able to access those particular two wires by first removing AC unit, and fishing a new positive wire the couple feet from the small ceiling hole for wires back towards AC opening in ceiling, attaching to positive wire of that circuit. Hmmmm.......maybe get lucky by cutting out that dob of factory white silicone looking stuff plugging hole where wires exit, jiggle positive wire around and see if it wakes up.

Again, thanks for all the GOOD input/ideas! I DEFINITELY can count on that here to get the mental wheels and thought process CORRECTLY engaged in the right gear.

BTW XJOK2PLAY, 12v more fun to 'play' with......it don't bite like 110v.......plus, house current has always been confusing to me, since I've always dealt with 12v automotive type systems. I get confused even replacing a switch or plug recepical...... like,what the hecks up with three wires.

[3Phase]

I See The Light!

Hey, Brant, you've got a manual and schematics for your R.V. and that's, like, so totally cheating! Unless someone did something completely brain-dead when they ran the wires there should not be any hidden junctions or splices in the +12v or ground wires.

Like checking Bentley's ignition just look at the schematic, reevaluate your series circuit current flow basics, then start checking junctions and switches and voltage drops at/across the fixtures because one of them is probably the culprit. If it's a cruddy switch or junction that'll beat the heck out of pulling the AC unit and running new wire nine ways to next Sunday because they probably used urethane, not silicone, to glue the AC unit into the roof.


.

[motoman]

If it were to come to that, the AC unit is gasketed with the inner sheet metal of unit on inside being bolted to outside unit.
The 'trouble' lite is first one in a group of five total on that circuit, all located from top view of trailer, and proves out when that circuit fuse is pulled when rest of lites are turned on that circuit. Those wire connnections showed a suspicious 12.3v compared to a nearby lite of 13.2v(inverter float voltage). As it turned out, the positive wire is the culprit with any load....dropped to 1.4v when light load was added to circuit. It's (continious?) grounding wire work fine for test in post#26.
If it weren't for that lite being a central overhead area, would'nt much matter whether it worked or not.

[3Phase]

Say What?

If it were to come to that, the AC unit is gasketed with the inner sheet metal of unit on inside being bolted to outside unit.

Well, at least that's something. Murphy would've urethane'd the gaskets and flanges when the AC was put in the roof and you'd have destroyed the R.V. trying to take it off.

The 'trouble' lite is first one in a group of five total on that circuit, all located from top view of trailer, and proves out when that circuit fuse is pulled when rest of lites are turned on that circuit.

I think I've lost the plot somewhere. If the wire feeding the first light is bad, none of the lights downstream can work either. Is that what's happening or is it just the first light?

Take some pictures of the lights and scan that schematic!

Those wire connnections showed a suspicious 12.3v compared to a nearby lite of 13.2v(inverter float voltage). As it turned out, the positive wire is the culprit with any load....dropped to 1.4v when light load was added to circuit. It's (continious?) grounding wire work fine for test in post#26.
If it weren't for that lite being a central overhead area, would'nt much matter whether it worked or not.

Hmm... I'm still trying to figure how the wire to the first light can be bad but still allow the other four lights in the circuit to work.

What Should Be:

The wires run directly to each light:
+12v ====(L)====(L)====(L)====(L)====(L)=== Ground

Check/fix the connections at the first light and Robert is your mother's brother.


What You Have Described:

The wire may run through up to five hidden junctions and tee over to each light:
+12v ====T(L)====T(L)====T(L)====T(L)====T(L)==== Ground

Some bean brain(s) cut up perfectly good wires to add hidden junctions inside the walls and ceiling. This makes no sense at all. Sure, it's completely possible but it costs extra time and money. It might even be a total code violation depending on where the R.V. was made and sold because it'll light 'stuff' on fire when a junction goes bad inside the wall or the ceiling and turns the wiring into a space heater!

.