My house batteries are showing well over 12 volts when not connected to the charger, but for some reason I have no 12 volt in the coach. Also, my inverter has started turning itself on automatically. When I reconnect to shore power the inverter causes the lights to flicker. Also, after that happens I can't get any readings on the old Audit system. That seems to continue until the shore power is disconnected and then reconnected.
Another symptom that may or may not be related is that my boost switch doesn't seem to work anymore. We're parked for a week or so, so I have time to poke at a few things. Any suggestions as to where to start?
David,
"A little over 12 VDC" is not any good if you are plugged into shore power and the inverter/charger is working. Should be 13.0-13.2 VDC in float (once charged) and up to mid 14's in bulk mode.
Check voltage at the chassis battery as well.
If battery voltage is too low, there is not enough power to pull the boost relay in.
Brett, I had over 13 volts at the batteries with shore power disconnected but engine running. Should I disconnect shore power, engine off, and then check battery voltage?
Yes, with engine running, the alternator should charge both battery banks.
Turn off the engine and let it sit a few minutes, then check voltage before plugging in. Surface charge will dissipate quickly, leaving a fully charged battery reading 12.7 VDC.
Plug in. If inverter/charger is working (assume that is what you have), voltage should go right up to 14 VDC, then drop off to low 13's after the batteries are fully charged.
if you are looking for the actual battery level of charge, 1st remove the surface charge.
David,
Are you saying your 12vdc lights are not working except when your inverter is plugged in?
Pamela & Mike
David, I'm not sure where your main 12v switch is (ours is in the front step well) but make sure it is on. Mine got switched off accidentally once, half hour of panic later Susan asks the obvious, "Is that 12v switch on?" Good for her.
Roger
We had our disconnect switch accidentally turned off when loading things into the coach. That was a real scramble for a bit. Electrical problems are always so troublesome, just have to be calm and start running thru the could be's. Process of elimination. Stay calm and have a great day ---- Fritz
Main 12V disconnect switch (salesman's switch) is by the door and is turned ON. The interior 12V lights don't work unless we are plugged into shore power. I suspect that the inverter has something to do with the problems, since it is now behaving differently than it did this summer. Weather permitting, tomorrow I'm going to crawl into the basement and turn the inverter off with the main power switch rather than with the remote. Then I'll see what happens.
David,
Check to see if your unit has the main breaker tripped that is hid in the hole in the top left hand side of the service bay. I have a pic. that I will post if I can find it so you will know what to look for. On our '92 we also had a main line fuse between the battery and the 12vdc panel in the basement.
Pamela & Mike
David,
Here is the breaker that I am talking about. It just took a while to find the pic. this is off our '92. In fact this is the same location on our '97.
Pamela & Mike
Our coach has three 90-amp 12-volt large round circuit breakers that are mounted next to each other near the top under a white removable bay wall cover.
Two of the breakers are automatic reset. One is manual reset with the reset button located on the back of the breaker. To reach the backside reset button, Foretravel drilled a hole in the bay wall so the reset button can be reached from the other side of the wall. The photo shows this manual breaker reset.
One of the wiring diagram sheets shows what is under the white cover.
To me it sounds like one of your house batteries has gone bad. To properly check them you will have to completely disconnect them from each other and the coach.
Well, thanks to PamelaMikeBarryCindy, I've crawled all over our coaches and never noticed that reset button!
jor
To get back to my original question: why do I not have 12vdc unless I'm plugged in? I had noticed the hole but didn't connect it to the electrical stuff on the other side of the wall. I tried pushing the button, but it didn't move, so I'm assuming that it probably is okay.
I'm plugged into 50A, and just tried starting the generator. Flickering lights, but otherwise nothing. I suppose the next step is unplugging and disconnecting batteries, then checking each one. That may have to wait for a bit until I warm up some. The temperature may be 40, but so is the wind.
Maybe an inline breaker between your converter and the batteries. I know that you replaced your converters, so maybe could have a bad connection somewhere. Sounds like your converter is not charging the batteries. Also might have a broken connection there close to the batteries
Red, I'm starting to wonder about that, too. I just disconnected everything, and both house batteries were at 12.96 volts, measured separately and disconnected. I didn't crawl under the coach, but I'm wondering if the isolator may have something to do with this. Since I have power when plugged in, obviously the 120VAC is being properly turned into 12VDC. Since the batteries show full charge I would assume that they are, in fact, being properly charged when plugged in.
I'm thinking that my next test will be to leave the 12v stuff on and flip the 50A breaker, then check the batteries. Jo Ann can tell me how quickly the lights give out.
David,
Your 300 may be different and I hope im not making myself a fool with this explaination and you may already know this.
This is how I understand the electrical systems operation. If I am a fool, be gentle as I am corrected, I only want to understand :))
The 12v system is a stand alone system. The charger-inverter, solar or engine, charges batteries. The isolator only works with the engine, 110v does not hook to the isolator.(this was my concern) Solar controller and charger hook directly to the battery.
The shore power is completely seperate to your 12v system except through the charger.
If you had an inline fuze tripped, you would not have any lights, since their dim or flicker it makes me think of an intermittent issue, like a loose or corroded connection.
Our 88 had the same issues flickering, gen no start. Turn on the power lights were back on. As it turned out the salsman switch and a couple loose battery connections were the cause..
Hope this helps ^.^d
John,
Here is another thought to go along with your insight on 12 vdc. If your inverter/charger can't see a battery it can go crazy and cause the lights to flicker. Depending on where there is a bad connection, cable, or complete battery failure will determine if this condition will occur. If you run some of the inverters without a battery for it to fill the inverter can be damaged.
Pamela & Mike
I've become a bit confused after all the suggestions. Do all your interior lights work fine UNTIL your inverter is turned on? Is the inverter also the charger? If both of those are true then I would suspect the inverter/charger.
If both house and start battery banks are fully charged you may not see any reaction from the Boost switch. I had to replace my boost switch a month ago, however... there was no increase to start bank when I was on shore power and turned the boost switch on.
Craig
Where did you get the replacement boost switch, have a part number? I need to replace the ether start switch with a normal on off switch.
Roland
It is nice and sunny today, with temperatures in the upper 50's to lower 60's, so I decided to see what I could see about my electrical problem. Since a couple of other questions got added into my original thread I decided to start a new one.
ALL house 12 volt circuits work fine as long as I'm plugged in. As soon as the 120VAC goes away, though, all house 12V stuff is dead. The two house batteries were new less than a year ago, and show 13.87 volts while plugged in. After about 15 minutes of being unplugged they showed 12.6 or so.
The generator starts from the house batteries, and it will not start even when plugged in. When we get ready to leave Monday morning I'll try jumping it from the Jeep.
The light on the boost switch does not come on, nor does it seem to make any difference whether it is turned on or not.
I crawled under the coach to look at the isolator. It has three large terminals across the top with two smaller ones between them (L s L s L) and what look like two solenoids in the lower right part, two automatic resetting circuit breakers and a couple of plugs in the lower left part. Since I was by myself then I couldn't trace all of the wires, but it looks like the far left large terminals go to the house batteries. Does this make sense, and does it sound right?
It appears to me that the two chargers/converters are supplying the proper current to the batteries and coach stuff when plugged into 120VAC. Somehow, though, the batteries are not able to provide current by themselves. On the other thread someone mentioned the reset button that is accessed from the utility bay. I tried pushing it, but nothing moved, so I'm assuming that it didn't need resetting.
My thought at this point is that after lunch I'll shut everything off again, disconnect all batteries, crawl back under the coach and take off each connection on the isolator, clean it up, and retighten it. If that doesn't solve the problem, what should I look at next?
Could it be that the terminals on the 12v disconnect switch (the one in the stairwell) are corroded?
Might also check the main 12V breakers (or high current fuse - not sure what your coach has) to see if there's voltage across them (should be zero) Breakers get weak or fail over time.
And, of course, there's always the question of whether all the grounds, particularly the high current ones, are still good. Any connections exposed to the weather may need to be tightened or removed and cleaned.
Are you measuring the house batteries directly on the battery terminals? Might measure voltages with cables disconnected from the batteries after the surface charge dissipates (~1/2 hr), then measure current draw between ground cable and battery terminal with things in the coach turned off.
If voltages are still low after charging overnight and immediately removing the cable, I would suspect the batteries.
I'm back from crawling around under the coach. All connections were good. I cleaned off the top of the isolator and found what I believe is a brand and model number, Powerline PL1-190-3. I searched for that and found PLI-190-3, so I looked at it. The picture showed a much smaller isolator, with only three terminals on it.
We're scheduled to head back home Monday morning, and then head to Stillwater Wednesday morning. I'm thinking that maybe I ought to call Foretravel Monday morning and have them send a new isolator to the church in Stillwater. Does that sound reasonable? Maybe I should have them send all of the other things on that panel, too, so that while I'm underneath changing the isolator I can just do all of it and not have to crawl under again.
Any EE people here?
Dave, yes I have been measuring right on the battery terminals. It seems strange that I have 12V when plugged in, but not when not plugged in.
David, Does your coach have a transfer switch ? Some coaches have two, seems funny that 12V is available on shore but not on batteries, disconnect somewhere. Sorry can't be specific.
I would start with a voltmeter from pedestal ( including cord ) to isolator to inverter thru transfer switch. Got to be some point where current is not flowing.
Good luck.
Gary B
The isolator is just for alternator output-- nothing to do with shore power.
And, the ATS (Automatic Transfer Switch) is strictly 120 VAC (select only one-- shore power OR generator. If two ATS, the second would be for inverter). Again, no relation to your "no 12 VDC to coach except with shore power.
With shore power off, start at the battery with a voltmeter. Progress toward the 12 VDC fuse box and see where you loose power. Be sure to check ground side as well.
You are getting 12 volts from your converter/battery charger and no voltage from the batteries themselves. As Brett indicates the isolator should not be in that circuit. There has to be a break/loss of continuity between the chassis batteries and the 12 volt panel. I think those sre the circuits that you should be ringing out. The generator not starting on shore power also points to a major break in the flow of 12v from the coach batteries as the converter cannot provide enough juice to start the generator. The boost solenoid gets its coil voltage from the coach batteries as well. I would really focus on ringing out the 12v circuit beginning at the coach batteries. Interesting problem am eager to find out where the break is, not as eager as you I'm sure. Think I will study my 12vdc schematics maybe get a better understanding of your issue.
Roland
Kinda makes me wonder if the previous owner found some way to disconnect the coach batteries from the charger instead of replacing the batteries? If he did you'd have 12 volt DC power only when the charger has shore power. Your coach batteries are fully charged because the alternator charged them the last time you drove your coach... I dunno, that's all me wittle bwain can come up with! haha
ScubaGuy and I poked around a bit this afternoon. The boost solenoid is engaging and disengaging properly. The batteries are charging properly.
Roland, as I think about it, the problem has to be in some portion of the circuitry that is used ONLY when on battery power. I tried jumping the house batteries from the Jeep in order to start the generator, but that didn't help, either.
Scott, all was working fine until a couple of weeks ago. The current inverter and converters/chargers (2) have been in place since spring.
I got to spend a few minutes with David scratching our heads about his 12V issue. What I can't understand is the generator not starting. We even tried to jump it with his Jeep. There's a "click click click" but the generator doesn't turnover at all. In my very layman terms there's volts but no amps.
We pulled the cover off the 12 panel in the bay. There was an obvious 12V + & 12V - terminals. Between the two was 13.4V. There are two "breakers" toward the top, one I guess is self resetting, at each lug to the main 12V- terminal was 12.2-12.3V. The other one, which can be reset through the hole into the next bay, showed 13.4V. So my guess is that the one self resetting breaker is powered by the start battery, and the other is from the house batteries/chargers? Wish I had taken a picture. Everything in there seemed to be showing voltage.
I guess it's possible the battery chargers are able to keep everything going while connected to shore power but don't provide enough power to start the generator?
Did your jumper from Jeep go from Jeep battery to generator positive and to good ground ON THE GENERATOR?
If that did not work, try turning the generator over by hand to make sure it is not seized up.
Brett - we went from the Jeep battery to the one of the house batteries. Are you saying directly to the starter and a good ground? That might be challenging to get to, but worth trying.
My guess would be it's probably something in the panel beside the batteries where ScubaGuy was looking. There are a bunch of self resetting breakers in mine too and I've attempted to understand them several times but failed to, even with the drawings. As I recall several of them are identical. I'd probably swap the identical ones to see if the problem goes somewhere else. It's also possible there's a fusible link in the cable between the charger and the batteries. To test that I'd disconnect the battery terminals and test to see if the charger is sending voltage to the battery terminals. You already know the charger is sending voltage to the rest of the coach... so I dunno?
That would prove that the generator is OK and the issue is between battery and generator (positive OR on ground side).
I suppose it's possible the coach batteries could have a bad ground, and obviously the charger has a good ground which would explain what you're experiencing. I have no idea how that would happen but hey, if you run out of things to check.
I don't believe you have continuity from the coach batteries to the rest of the coach. There is an open or current limiting resistsnce some where on either the positive or negative side. Just my thoughts on the issue as you describe the symptoms. Believe your attempting to start using an external power source, the jeep, but jumping on the coach batteries proves the point. Seems to be current limiting as you heard a click.
Roland
Roland, I think you are onto something. My simplified view of the system is that the converters/chargers provide power to the batteries, which provide power to the coach, just like on the engine side. BTW, I don't have the 12V with the engine running, either. That's going to make for a chilly run back to Urbana Monday.
So, how are the electrons supposed to flow when there is only house battery power compared to how they flow when there is shore power? What's different?
BTW, the chargers/converters were warmer than ambient air temperature but not by much. The fans were either not running or so quiet that I couldn't hear them. When the temperatures have been warmer I could hear the fans when I opened either door to that bay.
Disconnect the coach batteries with shore power on and see if there's any voltage on the battery cables from the charger. If not you know for sure that you don't have continuity from the batteries to the charger but you do have continuity from the charger to the rest of the system.
The charger is probably only about 70 amps or so, which won't be enough power to start the genset without the batteries, but it has enough power to close the starter solenoid, which explains why you heard the starter solenoid click but the engine couldn't crank, even with another vehicle jump starting the coach batteries, which are already fully charged from the last time you drove your coach.
You're probably gonna find a blown fuse or tripped breaker in that panel beside the batteries. It's a confusing panel that I can't understand even with the drawing in front of me. I'd swap the identical breakers to see if the problem moves with one of the breakers. If you can find any fuses or fusible links you should test those too. Check the ground for the coach batteries also. I suppose it's possible they've come ungrounded somehow.
with shore power the converter provides power to the batteries AND provides power to the coach, different paths. As there is no drain on the coach batteries perhaps that is why the converter was only warm to the touch, not working hard to charge the batteries. Could be a bad ground off the battery circuit somewhere. From your observations it appears that the coach batteries are OK so something is loose, disconnected or blown. There are a couple 90 amp fuses that I would check if you haven't already and I would make certain that the battery disconnect switch is actually making contact, not just clicking. After that I would scratch my head and start tracing wires.
Do you have a gate to prevent engine coolant from heating domestic water? If you do I would make sure it was turned off to give maximum cabin heat. Closing the bathroom door will also help keep the front area warmer. I reversed the locking mechanism on our bathroom door and keep it closed and latched when driving, both in winter and summer.
Good luck, if you were here in Arizona I would be happy to help you trace out the problem. Am very curious as to what is causing your problem.
Roland
David, I know you have checked and the salesman switch in on. But have you checked to see if the salesman switch is working?
Larry
I just looked at the schematic again for the umpteenth time. The salesman switch is the biggest suspect. It appears by the schematic that it would give the symptoms that David has if it was turned off OR not making contact.
Roland
I don't think it could be the salesman switch. When I'm hooked to shore power and turn that switch off, all my 12v lights go out. All David's 12v systems work when he is plugged in. Also, I'm able to start the generator with my salesman switch off.
I could very well be missing something, but that just doesn't seem like it could be the problem.
Douglas, David said that he has an inverter and a converter/charger. I believe from his statement that his inverter and converter/charger are two separate units. I believe that your coach has an inverter/charger and no converter/charger. These two system function differently. I am not sure about David's Foretravel but on some motorhomes with a converter/charger, with using shore power, the converter powers the 12 volt system directly and at the same time provides a charge to the batteries. In those systems, when on shore power the converter will provide power to the 12 volt system even with the salesman switch is turned off. And, on some converter/chargers, they will function when on shore power even with the battery or batteries removed. Having said that, I am not sure how the converter/charger works on David's Foretravel.
Larry
Normal lead acid battery voltage is 12.6 , would suggest using a Volt meter and start snooping.
That's all news to me. ;D Yes, David definitely has a separate inverter and from his (converter/)chargers. Actually he has two chargers. Well, now I'm going to have to re-think this whole thing with that extra info.
That is what the OEM schematics show an inverter and a separate converter.
Roland
Keep in mind that the salesman switch only powers off the circuits that are not directly wired to the battery.
Very old style converter/chargers has two circuits, one to power circuits that could operate with dirty dc, notable incandescent lights, and one to charge the battery, which in turn provides clean dc power to tvs, radios, and other noise sensitive electronics.
Newer style converter/chargers were really chargers only. Smart chargers too. All dc power came from the battery, with no separate converter sourcing dirty power.
Latest update: I shut off all power to the coach, disconnected all four battery terminals on the house batteries, then turned the power back on. The battery cables showed 14.46 volts, which tells me that the charger/converter is working properly and the house batteries are being charged.
I turned the power back off and headed to the other side of the coach where I put a towel over the copper gas lines under the salesman's switch. Either the factory or a PO decided that four screws weren't sufficient to hold up a small plastic cover, so some sort of sealer was added. Once I got that cut I found that the whole underside of the switch is covered in black electrician's tape.
I put the cover back on, without adding more sealer, and went back to the other side of the coach. The batteries had been disconnected for 20-30 minutes, so I checked their voltage. 12.86 on one and 12.87 on the other.
I put everything back together and checked for any inside 12V activity. Nothing.
All the electrical tape around the switch seems suspicious to me, but maybe I am a suspicious type of person when it comes to PO's. I would have removed the tape and made sure the switch is functioning properly. Process of elimination.
Roland
My son is here, and he came up with another test. I put the meter on the battery while someone tried to start the generator. We wondered what happened to the battery voltage. The drop was only 0.04V.
Is this the schematic for your system?
Irwin
Kind of looks like it. The diagram looks like there are three large breakers, and I think I have only two. Maybe the third one doesn't look like the other two, though. This will bear more checking. I'm going to be home Tuesday, waiting for propane, so I can poke around a bit more then.
I'm betting that's factory. Here's a photo of mine. Same deal.
jor
Jor, that looks EXACTLY like what I found. I'll probably clean the tape off tomorrow.
Guys,
??? ??? ??? ??? ??? ??? ?
If you mount a switch in a potentially explosive (Propane) environment, you either need to use an industrial, sealed, explosive environment switch (= expensive) or you can use a switch that you already have and carefully seal it off from the environment (what Foretravel did in this case). And, the tape on the terminals is there to prevent your dropped (or in motion) wrench from bridging (+) 12Vdc from the bare switch terminals to the gas piping or other ground point, creating sparks and the potential for an explosion.
Just remember that 6% or less of all RV fires originate from defects in refrigerators and 94%, or more, are caused from other sources (many of which are poorly implemented or thought out "upgrades" from the RV's original design).
Neal
Can't drop a wrench on those terminals as they are on the "ceiling" of the Compartment. In addition they are covered and the cover has some type of caulking sealing the terminals. Maybe a bit of overkill. I would have used an insulating spray. Would still remove the tape to assure that everything was hunky dory as far as the switch was concerned. Then resell and cover.
Roland
I for one am eager to hear what the issue is with this coach, not as eager a Dave but eager nevertheless.
Roland
Just heard the weather forecast and it sounds like I can work on this today. I'm going to warm the coach up to about 80, then kill all the power and trace wires. That will include taking that tape off. After I'm done with the switch I'll retape it. After I know where wires go I'll reconnect the house batteries and see where the electricity disappears.
Since all is good when we're plugged in, the only inconvenience is when we're traveling. Yesterday we cranked the heat up to 80 while we were packing up. Once I unplugged, of course, the furnaces stopped working, but the engine heater kept us nice and toasty.
I'll report what I find tonight.
Dave, any progress on your 12 volt issue? Inquiring minds want to know.
Roland
Well, no. The weather hasn't been very cooperative, and we were supposed to head down to Stillwater Wednesday. Unfortunately (or fortunately) the air compressor decided to quit on us, so we're stuck here at home until a new compressor and air dryer can be installed, which won't be until Tuesday. Tomorrow looks better than today, and Monday looks better yet, so we decided to spend today cleaning inside the coach.
I have been thinking about the problem, though. One test I want to run is to have some 12V stuff on, then have Jo Ann turn off the 120V while I measure the voltage at the batteries. Then I'll disconnect the batteries and have her turn the 120V back on. I talked to my b-i-l who is an electronics tech who worked with battery stuff for many years. He is also somewhat suspicious of the batteries, even though they were new last spring. I'd like to leave them completely disconnected for a couple of hours and see what they show.
He wondered if the charger/converter had two outputs - a charge circuit and a converter circuit. The answer is no. Each box has one + and one - lead coming out. The two outputs are in parallel (just like the old MagneTek one were). I haven't followed the wires completely, but it looks like those leads go straight to the batteries and then off to the rest of the coach.
One interesting thing we've found is what runs on the house side that I thought was on the automotive side. The power seats and dash radio are on the house side. No listening to the radio while driving until this is fixed. I had moved the navigator's seat forward while rotating it, and forgot to put it back. Jo Ann complained about the lack of leg room, and that's when I found that my seat wouldn't move, either.
Certainly a good test to charge, disconnect, and test the resting voltage of the batteries but I have been wondering about the battery cables. We all know to keep the ends clean for good continuity but that is really only half of the connection. The other half is the crimp inside to the wire which you cannot see. It's quite possible that sometime in the past 20 years these cable ends got pretty covered with acidic battery deposits that may have worked themselves inside to the crimp area. Cleaning would only remove the exterior deposits and combined with time a high resistance maybe the result and this does fit the symptoms. So once you reconnect the batteries back up, check for a voltage with a meter connected with one test lead on the battery and the other at where the cables terminates -which would be under the white cover on the wall that is to the left of your batteries. You will need to check both the positive and negative cables. If access to the other end of the cable is difficult you can also just use a needle probe (or safety pin) on the voltmeter to poke through the outer jacket of the cable. Hope this helps.
John, that thought has been going though my mind some, too. The best solution would be to replace every cable and end with all new, but that isn't going to happen. What gets me is that all was working fine the last time we drove the coach, and now it doesn't work.
Kb0zke,
Great time to get the wiring diagrams out along with a reasonable DVM and start trouble shootin, surely the problem will appear under normal situation when it worked before.
Should be reasonable to locate where it fails. ?
Sounds like a fun challenge.
FWIW
For the last few days I have been wondering if when you tested your battery voltage you also tested from + battery post to frame of coach.
Seems like that would go some way toward telling you something about the cables.
As well as a resistance check from the battery negative to chassis ground.
Roland
FIXED!!! The schematic above shows three fuses, and I found only two under the white panel. The third one, it turns out, is located underneath the converters/chargers. One of the leads was somewhat loose. I tightened it up (power was off), turned the power back on and all looked good. Then I flipped the 120VAC off and the furnaces kept running. Lights were on in the bays that were open. Problem solved - I think.
As I think about it, I may want to add a lock washer to that connection, but that can wait for a warmer day.
Thanks to Kent Speers who helped point me at that connection. I had assumed that because the 12V stuff worked when plugged in all of the converter/charger area was find. Not so.
David,
Great! If you have a camera handy, please shoot a photo of the location and post it. Sure would be easy for anyone to miss. Good job.
Pierce
Will do. It is 50 and sunny out, and we're going to straighten out the bays a bit, so it will be easy enough to take a couple of pictures and post them this evening.
Here are a couple of pictures. One shows the two chargers/converters sitting on the shelf where the old "battery cookers" sat. The other shows the missing breaker underneath the shelf.