All outlets work, fridge works, interior lights don't work

[jsenger]

Hello,

We just got our 2016 Thor Hurricane 34J this past weekend, and the day after we drove it home we discovered that when it isn't plugged in, or generator running, the lights won't turn on. The fridge, televisions, outlets, etc. all work. None of the lights do though.

I've checked:
1. Breakers are not tripped.
2. GFCI isn't tripped.
3. Battery disconnect is not switched - keep in mind  everything that is working from the battery.
4. Checked the fuses. Those all look fine.
5. The voltage check is showing 12.6v off the converter.

I'm really confused. Any ideas on what else I can check?

Thanks!

Jon

 

[glen54737]

I have a master lights on/off button not sure if that would cause this or if you have one.
But it sure seems a 12v problem.

 

[Back2PA]

Just to clarify, when you are not plugged into shore power and when the generator is not running:

1) You do have power to the outlets?
2) The fridge does work?

If yes, this means:

1) You have an inverter powering the outlets
2) You have at least partial 12V power as it takes 12V power to run the fridge whether running on propane or 120V

12.6V off the converter means the converter is not operating, that is fully charged battery voltage only. Converter voltage should be in the 13.5V-14V (approximately) range, but definitely not 12.6V. However, when are you checking the voltage at the converter, when you are not plugged in or genset not running? If that is the case, there is no power to the converter so 12.6V would be correct as it indicated battery voltage only

More details would be helpful

 

[jsenger]

Yes, to clarify:

When I am not plugged into shore power, and when the generator is not running, I have power to the outlets and the fridge. It's a residential fridge, not propane.

I'm not getting 13.5 for sure. Once in a while I can hear the converter fan kick on for a split second and then it goes off again. It doesn't run full time. Should it?

 

[grashley]

Welcome to the Forum!

When NOT plugged in, the converter is off, so the battery should read 12.6V, meaning full charge.  It does not matter too much where you read the voltage.

When plugged in, you should measure 13.5V  or higher, as you are actually reading converter output.

Most lights run off 12V battery power.  If lights do not work, flip the battery disconnect.  The label / wording is sometimes wrong or very confusing.

For clarification, a CONverter takes 120VAC and converts it to 12VDC to charge the battery and run 12V stuff.
An INVerter takes 12VDC and inverts it to 120VAC when shore power is not available.
Virtually all campers have a converter.  Few have inverters, but clearly yours does - to run the residential fridge.  The fan you hear is probably the inverter, not converter, unless it is a single unit that does both.

 

[Back2PA]

Yes, to clarify:

When I am not plugged into shore power, and when the generator is not running, I have power to the outlets and the fridge. It's a residential fridge, not propane.

I'm not getting 13.5 for sure. Once in a while I can hear the converter fan kick on for a split second and then it goes off again. It doesn't run full time. Should it?

OK , we know then that you have an inverter and it's getting power from the batteries. But no other 12V is available until you start the genset or plug in? Perhaps the master disconnect switch in the status panel area?


Re the fan, often they are load dependent so might be normal.

 

[jsenger]

@back2pa - I'm not sure how to test for 12v anywhere except for the lights. I can confirm that no lights anywhere work unless the genset is on or it is plugged in. I have no idea what I'd be looking for with a master disconnect. I don't see anything like that.

@grashley - Thanks! Ok, so that makes sense. When I'm plugged in it does read higher, but I'll confirm. Regarding the batter disconnect, it is a rocker switch that auto centers. I push it towards the ON, and it auto-returns to center position. Flip it to STORE and it auto returns to center position. There is no change in any available power regardless of what I do with that switch. No clicks, nothing. Still have power to the fridge and outlets regardless. Sounds like I need to try to find the converter...I only see one unit. It is a Xantrex Pro XM 1800. I think, after googling, that is an inverter...

edit: Ok, the converter is the one with the fuses and breakers. Still wondering if I have a crazy issue with the battery disconnect. Any way to test that? Feel like I have and nothing happens...

 

[Gizmo100]

Welcome to the RV forum

Do you know if the inverter was factory installed or done by the previous owner.

I'm wondering if it was miss-wired but never noticed until now.

 

[Frank B]

Can you check with the previous owner or dealership? They may know right away what the issue is.  It may be a 'feature' rather than a fault.

 

[John From Detroit]

Battery--fuse or breaker---Switch---Fuse panel and converter or inverter/charger---

Fuses in panel---(Optional switch or switches)---Switch-light.

The first Switch (in the battery line) is a master cut off and it and the fuse/breaker may be swapped
"The braker could be tripped
If you have an inverter/charger it may be connected BEFORE the cut off switch.

On my RV several lights have both a "local" switch (On the light fixture) and a wall switch..or two.

 

[Alfa38User]

Jsenger wrote:

Regarding the batter disconnect, it is a rocker switch that auto centers.

The NORMAL battery cutoff switch is NOT usually a spring loaded switch. A spring loaded switch is often used to temporarily bridge the house system to the coach 12V system to help with starting with a dead or weak coach battery or starting  the generator if the house batteries are low.

The battery cutoff or disconnect switch should simply turn on or off. It may be labeled "Store" and "Use" or some other equally confusing name. You may be able to hear a big relay clicking when using that switch. It is often located right at the entrance door on bigger coaches or may be on the dash on some class C units.


It is often referred to as a  "Salesman" switch due to the habit certain salesmen have to use it to  turn the interior lights on and off rather than using the individual switches each time when showing the vehicle. Then again, it could also be a spring loaded switch provided the manufacturer provided the proper electrical wiring and latching relays to do so, you never know!!!

 

[ChasA]

I have to disagree with Stu concerning the disconnect  switch. A lot of RVs use a momentary switch to operate a latching solenoid relay to connect and disconnect the house batteries.  My Winnebago has this arrangement for both the house and chassis batteries.  An advantage of latching relays is that they only use power when switching states. Also, the boost switch has to be within reach of the driver.

 

[John From Detroit]

Jsenger wrote: The NORMAL battery cutoff switch is NOT usually a spring loaded switch. A spring loaded switch is often used to temporarily bridge the house system to the coach 12V system to help with starting with a dead or weak coach battery or starting  the generator if the house batteries are low.

In many RV's the battery cut off IS a 3 position spring loaded return to center switch. The solenoid is a magnetic latching device. push USE/lConnect/On and it moves one way and makes contact You will hear a CLUNK if it's not too far away.
Push it the other way and again it ClUNKS but it moves the other way and disconnects

Mine only clunked on disconnect.. I fixed it.

 

[jsenger]

Everybody, thank you for your feedback and help on this! I wanted to update as I found the issue last night while taking my voltmeter around from the battery to the 50amp fuse and breaker in the battery compartment for the house batteries. I started looking around behind the batteries and found that the power to the 50amp breaker was stuffed behind the batteries and never connected! Once I connected that, the cut off switch works fine and I'm getting 12v all over.

Thanks again - maybe this will help somebody else down the road.

 

[grashley]

That is the first thing about this that makes sense!!!  Glad you found a FREE and easy repair.  Thank you VERY MUCH for reporting back!!

 

[Chakara]

Yep - my head was spinning on causes.  Thanks for letting us know - problems like that are hard to diagnose on a forum when the person on the other end doesn't "get" a voltmeter

-Kyle

 

[John From Detroit]

Thank you for letting us know.  Far too many do not.