RV dinette light wiring questions

[rvshrinker]

Finally getting around to trying to replace this. OK, I procrastinated, used duct tape, and then it all fell apart (down) on yesterday's drive. When it fell a lot of the wiring came apart.

There are two lights. The two lights are connected by two white wires which are joined by a clamp connector. The lights are also connected by two black wires joined together in a twist, which I think came out of the clamp connector which is still attached to the ceiling. There is a third black wire running from the switch to the twisted black wires.

Coming out of the ceiling is a green wire, attached via a clamp connector to a black wire that clearly goes into the switch, and a white wire which I think goes to the white clamp connector.

Does this all sound correct? I'm not sure why there are two black wires coming out of the switch and why they both connect to black, and not white.

[enblethen]

Or a switch!
Run a meter lead to the shell of a close by light, set meter to resistance to check if the ground is good.
Next, change meter to a 20 volt or so scale. put one lead to shell of adjacent fixture, touch other lead to line (green wire0 to check for voltage.

[rvshrinker]

i found my voltmeter and can’t detect any voltage at the wires. I also can’t detect any voltage in the ceiling where I can tug on the wires gently and hear them rustling around. Other LED light fixtures and wires in the ceiling seem to generate a response from my voltmeter.

This suggests either a blown fuse, or something worse, like a wire getting pulled apart behind the ceiling, right?

[enblethen]

Yes, most of the switches will be rated something like 3 amps at 120, so it should work on a 12 volt DC, load of about the same amperage.

[rvshrinker]

enblethen wrote:
Switches are readily available for most fixtures. Check your local Ace, Blue and orange box stores.

That's a good idea, and a voltmeter. Since the light is 12v any switch rating should do, right?

[coolmom42]

rvshrinker wrote:

enblethen wrote:
The OP has a green wire that is his 12 volt DC positive, which connects to a black wire on switch. The second black wire from the switch goes to each of the black wires from the lamp sockets,(three blacks connected together), the two white wires from the lamp sockets connects to the white wire in rig's wiring.
Very common RV's 12 volt systems do not follow any recognized wiring color codes.
I like the use of crimp connectors over wire nuts. They stay in place better in high vibration situations.

This is what i thought. However when I hooked it all up, nothing worked. The switch wasn't designed to be taken apart so I'm improvising the reassembly. That said, I bypassed the switch by touching the black/green from the ceiling to the black wires on the fixture. Reconnected the whites. No dice. I don't see that a fuse is out and since the light doesn't work I can't tell which fuse it should be, only which ones it is not.

Next step some kind of 12v voltmeter?

YES a voltmeter is pretty handy. Just pick up a cheap one at Harbor Freight or Walmart. You don't need a $1K Fluke to do RV wiring, thank goodness!

[enblethen]

Switches are readily available for most fixtures. Check your local Ace, Blue and orange box stores.

[wnjj]

rvshrinker wrote:

wnjj wrote:

enblethen wrote:
Step 1: connect green straight to the black wires from fixture
Step 2: Are the lamps LEDs? Yes, possible polarity issue. Reverse black and whites to lamp holders:
Step 3: Get 12 volt test lamp. Make sure you have 12 volts to the fixture.
Step 4: verify that there is not another switch in circuit.
What part of the NW are you in?

x2 on step 4. From the original description it sounds like maybe the switch is on the light fixture itself? If that’s the case, the black wires may have been all wired to the same mushroom connector, intentionally bypassing the switch there and there’s another some place else.

Can you explain that again in a different way?

The switch is part of the light fixture. When the fixture fell, the switch fell apart and a little plastic tab broke, so while I can put it back together it's not easy. Once it's together it seems to hold. I might just have to buy a new fixture to get a new switch. But right now I'm trying to figure out my wiring. I don't see any other switch on the fixture or in the wiring.

In our truck camper, there is a wall switch that turns on an overhead light, but only if the switch on the light itself is turned on. The switches are wired in series. Is there a wall switch that runs that light or only from the fixture itself? If there’s a wall switch I was suggesting that the fixture switch was possibly bypassed by shorting the incoming power, both switch wires and the black light wires together.

[rvshrinker]

wnjj wrote:

enblethen wrote:
Step 1: connect green straight to the black wires from fixture
Step 2: Are the lamps LEDs? Yes, possible polarity issue. Reverse black and whites to lamp holders:
Step 3: Get 12 volt test lamp. Make sure you have 12 volts to the fixture.
Step 4: verify that there is not another switch in circuit.
What part of the NW are you in?

x2 on step 4. From the original description it sounds like maybe the switch is on the light fixture itself? If that’s the case, the black wires may have been all wired to the same mushroom connector, intentionally bypassing the switch there and there’s another some place else.

Can you explain that again in a different way?

The switch is part of the light fixture. When the fixture fell, the switch fell apart and a little plastic tab broke, so while I can put it back together it's not easy. Once it's together it seems to hold. I might just have to buy a new fixture to get a new switch. But right now I'm trying to figure out my wiring. I don't see any other switch on the fixture or in the wiring.

[wnjj]

enblethen wrote:
Step 1: connect green straight to the black wires from fixture
Step 2: Are the lamps LEDs? Yes, possible polarity issue. Reverse black and whites to lamp holders:
Step 3: Get 12 volt test lamp. Make sure you have 12 volts to the fixture.
Step 4: verify that there is not another switch in circuit.
What part of the NW are you in?

x2 on step 4. From the original description it sounds like maybe the switch is on the light fixture itself? If that’s the case, the black wires may have been all wired to the same mushroom connector, intentionally bypassing the switch there and there’s another some place else.

[enblethen]

Step 1: connect green straight to the black wires from fixture
Step 2: Are the lamps LEDs? Yes, possible polarity issue. Reverse black and whites to lamp holders:
Step 3: Get 12 volt test lamp. Make sure you have 12 volts to the fixture.
Step 4: verify that there is not another switch in circuit.
What part of the NW are you in?

[CharlesinGA]

rvshrinker wrote:
The green from ceiling connects to black using a connector, like a wirenut, but squeezed closed with pliers. From there a short black wire that is supposed to go to the switch. It has a unique end which is how I know that.

The fixture itself has one black wire from each light, and one black wire from the switch, and all the of those are twisted together. It's possible as wnjj said that those just need a wirenut or tape and don't go in the green/black connector.

So current goes green to black to the switch, then back through white?

Many electrical and electronic people call these "mushroom splices"

Charles

[rvshrinker]

enblethen wrote:
The OP has a green wire that is his 12 volt DC positive, which connects to a black wire on switch. The second black wire from the switch goes to each of the black wires from the lamp sockets,(three blacks connected together), the two white wires from the lamp sockets connects to the white wire in rig's wiring.
Very common RV's 12 volt systems do not follow any recognized wiring color codes.
I like the use of crimp connectors over wire nuts. They stay in place better in high vibration situations.

This is what i thought. However when I hooked it all up, nothing worked. The switch wasn't designed to be taken apart so I'm improvising the reassembly. That said, I bypassed the switch by touching the black/green from the ceiling to the black wires on the fixture. Reconnected the whites. No dice. I don't see that a fuse is out and since the light doesn't work I can't tell which fuse it should be, only which ones it is not.

Next step some kind of 12v voltmeter?

[D_E_Bishop]

Also called Bell Connectors.

[wnjj]

The inter webs calls those connectors “closed end splice connector”.