12v lighting issue... Could use some help :) (32BHDS)

[BiggyJ]

Not sure where to put this. Move it if it is not where it should be.
Thank you.

2007 Keystone Hornet 32BHDS
Power Converter PM3-55-MBA

OK... so I hate trying to figure out electrical issues in my 8 mo. (07) “new to me” travel trailer.

This seems odd to me but may be a common lighting issue to someone here.

Battery: 13.7v
Control panel: All connectors with wires attached: 13.2v on fuse output side.
Lights in bedrooms, bathroom and the slide-out will come on bright and as normal.

The outside door light, the above kitchen sink light and the three lights that are in the center of the trailer and operate off their own switch, I'm having problems with.

The outside door light and the three lights that are in the center of the trailer run by one switch plate. One switch for outside light and one switch for the three lights that are in the center of the trailer.

The above kitchen sink light has it's own push button switch mounted on it.
The three lights that are in the center of the trailer have their own switch as well but we just always leave the switches on and use the switch panel that controls them all.

What they are doing: Started awhile back, flickering a bit, getting dim, (about 40% brightness) and every now and then, just go off. All of them.

Now: sometimes, after turning on, they will come on slowly like the voltage is building up, while flickering.

Sometimes they will not come on right away at all. I can leave the switch on and sometimes they will come on within a few seconds and sometimes they will come on 5-10-15 minutes later. And then they may just come on instantly at full brightness.

Wiring and switches: switches seem functional when testing for continuity but why the hell I can put my DVM test leads across the two terminals and get 12 volts is new to me. I'm just used to the good old -12vdc and +12vdc

In other words, one switch terminal has -12 on it and the other +12. And that’s the way it’s always been I guess. Seems like when the switch is closed, that would be a direct short! Guess not ?

All internal lights are 12v.

Things I am curious about:

Do all lights go through the power center or are the ones that always work hooked up directly to the battery?

Or should ALL wiring come in to the control panel from behind the CP mounting plastic box?

Anyway, I sure would appreciate some help from someone. Pain for my wife to do the dishes with a flashlight.

Also, please note that the Power Converter PM3-55MBA hardly ever comes on now. Matter of fact, I think I remember hearing it come on only twice in the past few days.

Thank you,
John

PS – Other than your direct response help here, It would be very nice to have a wiring diagram for this TT. And possibly the correct way to test inverter/converter.

[jimlj]

BiggyJ
I'm kind of lost on your discription. Are all lights controlled by one switch, or are they controlled by different switches from one place?

If you are putting your leads from your DVM on the two terminals of a switch, you should read 12ish volts with the switch in the OFF position. With the switch ON, you should read 0 volts across the terminals. A DVM may show milli volts with the switch on, but if you are reading anything over about .5 volts you have a bad switch.

If you have several switches at one place, check the voltage on the common wire to the switches. You should have 12 volts between the common connection and ground. Also check the voltage across the terminals of your fuse. It should be 0 volts. (maybe .5 volt on a DVM) If you are reading any voltage, you have a bad fuse or fuse holder.

When your lights are dimming check for voltage across the fuse or switch(es). If there is a common connection at several switches check for fluctuating voltage between that point and ground.

[Sam_Spade]

BiggyJ wrote:
Actually I was thinking about getting out one of my lab power supplies and feeding the circuit with that to test it But I have not done it yet.

BAD IDEA.
One wrong connection and sparks will fly.....or worse.

[Sam_Spade]

BiggyJ wrote:

I'm starting to get concerned about the power supply now.

Save that for another day.
It has NOTHING to do with the original problem.

It is likely that the problem devices are all fed from a common +12 point (fuse maybe) OR they all connect their negative side to a common ground point.

Some wire tracing is going to be necessary here. You have a loose connection somewhere.

[BiggyJ]

Actually I was thinking about getting out one of my lab power supplies and feeding the circuit with that to test it But I have not done it yet.

Wife wants to go into town so I guess I'll get back to you guys later today.

Have a great day,
John

Millry, Alabama.

[Iraqvet05]

I also suspect you have a ground issue. Take a long jumper wire and run it from one of your lights (ground side of course) to a good ground and see what happens.

[BiggyJ]

Rolling Condo wrote:
Check connections especially the ground side.

Where exactly?

Behind control panel container box, under trailer, at battery or somewhere else?

Thank you

[donn0128]

Either a bad ground or a loose wire.

[BiggyJ]

OK... above kitchen sink light. The one that works with it's own switch, regardless of weather the panel switch by the door is on or not.

When I first tried to get a voltage reading, I read only around .x voltage. Then it raised to 4.xx.

Switch on. No voltage with switch off.

OK... other lights.

No voltage present with switch off.
When switch is turned on, voltage is random. Up to about 8v one second and down to .x to 0 the next.

[BiggyJ]

OOPS... let me try those suggestions and get back to you. Gimi 10-15. 🙂

[BiggyJ]

Well... best I can tell, they are. They are the only ones not working. All fuses are good and voltage is present on BOTH sides of the fuses. (ALL 12v fuses)

I'm starting to get concerned about the power supply now. I never hear it come on any more. At least I do not hear the fan. Thanks. If you can please stay with me to help me it would be very much appreciated 🙂

[Rolling_Condo]

Check connections especially the ground side.

[drsteve]

Unless a previous owner messed with it, all of the lights should go through a fuse in the 12V panel.

Have you determined if the malfunctioning lights are on their own circuit?

Try measuring voltage when the switch is closed but the lights are not working. Is there power available at the light when it's not lit up?

Have you tried tightening all the connections? And checking all grounds?