No 12vdc Batteries are Charged/Charging

[Morich]

Originally Posted by tderonne

OP reported that she only hears the switch clicking, no CLUNK from the disconnect relay, when she uses the aux switch. That's where I'd be looking. A voltage check on both sides would be telling.

If they don't want the frig to stop working, doesn't that mean the battery disconnect has to be "ON"? When I turn my disconnect off, about the only thing I have left working is the CO and propane alarms.

[imnprsd]

* Aux stand for "auxiliary" power. ...But in the dash picture above I think that was a typo, because the Battery Disconnect Switch (BDS) only goes by another name called a "Salesman Switch," because it is located by the front door. I.e., the salesman (or owner) can kill the house battery voltage by turning this toggle switch off.

Note: It's a toggle switch because the BDS is a latching solenoid type. Meaning it will remain in the "latched" or "unlatched" position with a flick of the switch... and this is the clunking sound you normally hear, even from 20 feet away from where the BDS is located.

* AUX is normally called your "Boost Switch" because it boosts (jumps) your engine battery to your house battery and visa versa.

Note: You have to hold the switch down for the Boost Solenoid to bridge/connect the house battery to the chassis/engine battery; and when you release the switch the connection drops out (turns off).

If ALL my 12V lights were flickering I would do the following:

* Turn "off" the inverter/Charger and see if my lights still flicker?

==> The charger portion of your inverter maybe putting "noise" on the line; so remove it from the equation.

* If your lights flicker when you power on any individual light switch, then maybe if you have an LED light bulb plugged in that is your problem?

==> Some of these devices produce frequency problems that interfere with your TV signals, but if your lights are flickering then maybe the LED board is shorting out?

==> This summer my bedroom light was flickering and when I dropped the light fixture I found a hot wire had rusty wire connection nuts and the pig tail was rusty. So I rewired it and no more flicker! However, if all your lights do not work then you need to look at your power source as the problem.

If I had easy access to the BDS Solenoid, then you might look at these potential problems:

* Wiggle the BDS to see if it is loosely mounted to the metal wall. Why? Most BDS get their ground off this metal backing plate. And some owners even add a separate ground wire.

* I would check that fuse on top of the BDS.

* Check for loose nuts on the BDS and the Boost Solenoid... and inspect all wires for rust or poor contacts.

* I might even use a 10" battery cable you can pickup at any Walmart and jump the left pole of the BDS to the right pole. Then see if your dash lights work and you can start your engine?

If you suspect your house batteries are weak or sulfated, and you have water in each cell if they are FLA type batteries, then you might do the following:

* Use a pair of jumper cables and connect them to your toad battery and to your house battery. ...Did your lights say bright?

* Remove one of your 12V house batteries and just connect the system to the the battery you think is in better shape. ...Do your lights says bright now?

* Remove both batteries and clean/inspect your 200A house battery fuse. These things get rusty over time! ...Then recheck your lights with one of your house batteries.

* If you still are having a problem, remove both your house batteries and jump your toad battery to your house battery cables.

==> Typically, if you are seeing lights flicker and it is related to a bad house battery, when you load-test your battery (for free) at any interstate battery store or Napa and most Walmart/Sam's then your battery will fail, but not always.

==> Your battery hydrometer may even show a full charge, and that will convince you that your batteries are NOT the problem, but this test is not conclusive. It is just another data point that is slightly better then testing battery voltage with a voltmeter.

==> If you have a known good battery, then use it and see if your lights do not flicker and/or if your microwave or space heater does not bring your battery Amp-Hours to it's knees!

* After all this and you still have problems, then you might have to look at your Energy Management System (EMS) or Power Management System (PMS), but I would think there would be different symptoms if this board needs to be replaced.

==> To clarify: Your 12V ceiling lights are powered by your 12V battery. Your Charger/Inverter is just replenishing your 12V power, but as you found it can also mask an underlying problem... BAD HOUSE BATTERIES... that have an internal short. So I would bet money you just need to replace your house batteries if your BDS is good.

Last but not least, I made some additional comments to the solenoid diagram and will say this:

* The red dots are NOT switched 12V sources. I.e., 12V are always present on these connections.

* What does the Yellow Wire #16 connect to?

Good luck with your diagnosis.

And I like to suggest to everyone, that if their house batteries are located within a couple feet of their engine batteries... that you carry a 30"-36" battery cable... just in case the engine alternator goes out... and you need to jump your house batteries to your engine battery to keep your engine running for another 50-100 miles further... so you can drive into a repair facility vs. getting towed in.

[thumpergirl]

Ok, so...
I turned off shore power at post and in breaker panel in rig
I started engine (which starts just fine without the BOOST being used)
I then checked all batteries: starter 12.4V (it stays right around there, as I'm parked and only run engine about once a week for 1/2 to 45 minutes to charge); coach batteries both at 12.9V
I then completely disconnected the batteries from the coach and waited 2 1/2 hours and rechecked. All voltages remained the same.


I did remove the panel under the stairs to look at the solenoid. Watched a video about checking it but my access is a bit awkward and the ground screw is right behind the hot leads. Wasn't willing to risk creating a bigger problem, so didn't meter it. Lots of wires back there and bending over to reach in there is not real easy for me physically, so I did what I could. I took a photo, so if there's if there's a place I can meter without having to stick a probe behind everything to get to ground screw, please indicate it on the photo, if possible


I still don't understand about checking the BOOST switch on the dash (the one that connects starter and coach batteries to aid starting a low battery). I'm assuming I would push the switch in while metering (but with the ENGINE OFF, YES?)


Also the lights that are flickering are NOT LEDs...the only LED overhead that I have does not flicker.



More tomorrow....I'm done for today! LOL

THANKS AGAIN....back at it tomorrow

[Morich]

Okay, that sounds like a reasonable level for the batteries but the lights flickering brings up some questions.
What type lights are these? They are powered by 12 volt dc, correct? If burning, that means the battery cutoff switch is on as I have not seem one which was anything other than on or off! If they are not LED, can we assume they are incandescent, the older bulbs which has a filament/wire inside? Not a fluorescent fixture by chance? Fluorescent are kind of famous for flickering but not often found in RV and not very likely to be 12VDC, but it might be something added or changed at some point.
Is it only the lights which you notice trouble with flickering? Do other things like the water pump, ceiling vent fans, which are also 12VDC, work as they should?
I'm trying to pin down exactly what the problem is as whether it is the batteries not being charged or if it is something further into the RV like loose connections or if it is only the lights, maybe just a simple problem with the light switch.
On checking the solenoid and getting to the screw in back, that is not necessary as it does form a ground connection but the wire coming in to that point that is FM on the drawing is also ground. But the bigger point for testing is that almost all parts of the metal frame of the RV are ground, so putting one probe on any of the metal and leaving that one in place is usually good enough. Usually on our auto systems, the negative post of the battery is connected to ground, so that is one place we can almost always assume is a good ground connection.

[thumpergirl]

PS...I know what the BOOST switch does, just clarifying how to check it, considering that the starter battery seems ok. Verifying that with the engine off and AC off, I would press it while metering the batteries, yes?


oops...posted this before seeing your last reply....


am reading your reply right now

[thumpergirl]

So the lights that are flickering are the original type...incandescent (I gues), and they are 12V and work when I am boondocking. I had one set of the overhead living room lights changed to LED a couple years ago and they DO NOT flicker in any way or change brightness.

This entire problem with no 12V is recent. Everything was fine back in August when I returned home from WA. And the flickering only started within the last couple of weeks or so.
I notice that the dimming/flickering is more pronounced when, at this time of year, my heater is cycling (using the propane heater vs the electric heater). Don't know what would happen with fantastic fan, as I've not had it on lately. The air conditioner ran fine during the hot summer after I returned from WA; there was no flickering of lights yet.
As for the fact that no 12V after doing battery maintenance is probably more coincidence than anything else. I know the batteries are hooked up properly. I think it's just that after maintenance, I checked that everything was ok with 12V before going back to shore power and that's when I realized that I didn't have 12V. I have been on shore power since I got home, so had no reason to suspect anything until the lights started acting up.

So if I assume that my batteries are all good and disconnected from shore power, I have checked for any lights coming on while flipping the AUX switch (in step well) on and off. Nothing and absolutely NO sound coming from the solenoid in the back of the step well when pressing the AUX switch.

Ok that's it for now...I think....this old lady has to rest her tired back....NITE GUYS!

[Morich]

Good enough, get some rest and let it cook for a while. It will be there tomorrow.
I've got a big ball game to watch!!

[imnprsd]

Since the Boost Switch is a momentary switch that is "normally open" ...this switch does not fail that often..

When the BDS (Battery Disconnect Switch aka Saleman's Switch) at the door goes bad it shorts internally and that's could be your problem since you cannot hear it "LATCH."

==> When you touch the BDS is it warm?

The short through the BDS mount will draw all the current out of your house batteries and will leave your voltage below 11V (over some amount of time, depending on the short condition) when you turn your inverter/charger off.

There is no good way to test for an internal BDS short, because the BDS will still function. You just have to replace it and then see if your old batteries will hold a charge.

Or... you can by-pass the BDS... and then connect the left BDS cable to the right BDS cable using a bolt. (Also connect the other 12v wires.) ...And with your BDS out of the loop you can then check your lights to see if they flicker.

Note: Solving the flicker problem may lead you to isolating the BDS as the problem, but you need to be sure those other small wires are also connected after you remove the BDS.

Personally, it's much easier to remove the house batteries and then use a pair of jumper cables to your car battery, so I would do that first. ...And you might just need to unhook the positive cable (TBD) to make the jump to your car?

If you determine you need a new BDS, this is the one most people get:

https://www.amazon.com/INTELLITEC-01...omotive&sr=1-3

Alternatively, I have heard Kwickee Steps can also sort to ground. So if you are still looking beyond the more likely problem areas, then you might try pulling your step fuses and then check your lights to see if they are still flickering.

[Morich]

I'm going to drop out of this as things are in crisis here.
Our daughter has been doing chemo and now needs the operation but cancer is now standing behind heart attacks and car wrecks for the hospital space, so they are now having a problem finding that.
How did we let things get so crazy that cancer is not considered a crisis?
STUPID! UNCARING? SELFISH!

[tderonne]

12 volt lights could be flickering when powered via shorepower and the converter with no batteries smoothing/filtering the converter output.

This would happen if the disconnect switch isn't connecting the batteries to the converter.

Again, a quick probing of the disconnect switch with a multimeter or test light would tell if it's connecting.

[thumpergirl]

Originally Posted by Morich

I'm going to drop out of this as things are in crisis here.
Our daughter has been doing chemo and now needs the operation but cancer is now standing behind heart attacks and car wrecks for the hospital space, so they are now having a problem finding that.
How did we let things get so crazy that cancer is not considered a crisis?
STUPID! UNCARING? SELFISH!

Oh Richard! I am so sorry for this! Go take care of your family, your daughter...she is the most important thing right now! I am sending healing thoughts and peace to you and your family in this crisis. The world has gone mad, yes...and often those who need help the most are the ones suffering for the actions of others.
PEACE, HOPE AND LIGHT TO YOU AND YOURS

[thumpergirl]

Originally Posted by tderonne

12 volt lights could be flickering when powered via shorepower and the converter with no batteries smoothing/filtering the converter output.

This would happen if the disconnect switch isn't connecting the batteries to the converter.

Again, a quick probing of the disconnect switch with a multimeter or test light would tell if it's connecting.

I thought I'd taken a photo of the solenoid but apparently not. I will try to do that tomorrow and post it. As I said in a previous post, not sure about how to meter this, so once I upload the photo, maybe you or someone can indicate on the photo where to meter.
I can also test the actual disconnect switch in the step well. But, again, I hear absolutely no "clunking" sound when the switch is toggled on and off, which I used to hear quite distinctly.

And all the checks on my batteries show them good and charging from the converter, but no DC going through from batteries when not on shore power.

[Jim in SE Ks]

My 1998 Brave 35wp has A lot of breakers and fuses under the dash pad. Removwe 5 or 6 screws lowerpart of dash pad and lift carefully. If yours is like my '98 brave, afgter you lift the dash pad you should see all the fuse boxes and to the right of those could/should be a 40 Amp breaker. If its popped reset it. End of my problems. Hope this helps.

[thumpergirl]

Jim...THANKS....I will check those dash fuses tomorrow after Thanksgiving breakfast!
Have a safe and happy Thanksgiving everyone!

[mikf]

Do you have 2 12 volt batteries or 2 6 volt? I know they come with 12 volt but maybe somebody changed them to 6 volt. How many cells do you have in each battery? If only 3 cells maybe the batteries did not get hooked up properly after your maintenance.

[thumpergirl]

Thanks Mike. I have 2 deep cell 12V batteries, plus my starter. They are all connected properly.

[Morich]

Okay, time to think about this again as crisis is averted here!
For testing the battery disconnect switch, we need to look at simple first and remember what it does. It cuts off the power to most of the things in the RV which use 12VDC!
Some background on the thinking may help. When chasing wiring and looking at drawings there is one certain way to tell a lot about where the wires go and how important they are in the overall plan of things. Big wires are only rarely fed power by smaller wires as they design and use the large wires to carry far more load than small wires will. On these drawings the wire size and colors are on the drawing, with the smaller numbers being larger gauge wires! Battery cables are often number one gauge and then those large finger size wires feed other smaller wires. So the power from a battery will come in on larger and go out on smaller gauges to give you a good hint on which way the power comes from! You can't feed enough power to feed a big old battery cable through a little 16 gauges wire, so you know the power is running the other way.
So if you look at this drawing, the big, big 1-0 cable comes from the coach batteries to the mode solenoid but doesn't go through it but just meets a number 1, goes to the disconnect relay and if that relay is operated (turned on) the power comes out the right side on a smaller but still chunky #6 going to the breaker panel.
So about the quickest test for the battery disconnect switch as well as the disconnect relay is to turn on a light inside that you know is 12VDC (most are) and then flip the disconnect switch. If the light goes out, the switch is working and making the disconnect relay cut off the power!
The reason I did not worry it working very much in your case is that you probably are using 12VDC for things like the monitor panel lights and the frig controls and assuming you are not setting there in the dark all night without mentioning it?

We can know that the number 6 is still quite a large wire and that means it does lots of work and feeds a 55 amp breaker as well as 30 and 15. After a bit of thinking, we learn that a 55 amp breaker is a major player in the RV world, so it is very important!
In the case of the battery disconnect, it runs most of the items inside the RV!
So if is turned off as some have proposed, you don't get lights, fans, pumps or most any of the controls or monitor panel. you also can't start the generator as the starter power comes from that number 1 red cable coming out of the right side of the disconnect relay.
It is still possible that the converter is not charging the coach batteries, if that still looks like a problem but that is a whole different place and idea to check--if it still seems to be true.

[mikf]

Richard, to do the above test, is that with shore-power connected or disconnected?

[Morich]

For testing the "aux battery disconnect", I would prefer to leave the RV unplugged as a way to be sure but I "think" (without looking) that it would be the same. That leaves the disconnect working as just a simple switch would except that we have a small switch at the door that controls big current flow by using a "slave relay" setup.
The reason for using slave relays is just the physical part of the wiring, very much like the ignition switch on our cars. We need big cables from the start battery to the starter but we don't/can't run those big battery cables up to the ignition switch, so we run little wires that fit to the switch and let that switch control a relay (slave) to do the real work to carry the heavy load on heavy cables!
EDIT: I have just gone out to check how my RV works and the power is still there when the unit it plugged into power, so to fully test the disconnect relay we do need to unplug first-- at least on mine!
Does not pay to "assume", best to actually check as there are lots of different small points on RV.

[Morich]

Looking for the converter output and found this small snip.
The output of the converter does feed a breaker panel (in microwave overhead cabinet) and breaks down to a lot of small circuits at that point so testing without disconnecting the converter input 110AC will confuse the issue!