House Battery Balance Light

[michaeldterry]

Last weekend, while we were underway to Paradise Valley in Dawsonville, GA to meet up with Curtis Coleman (CCMH), the House Battery Balance light on the dash came on and stayed on until we were almost there (about an hour). We were running the generator (as we always do when underway) and had the refrigerator, two CruisAirs, two TV's and the satellite on.

On the way home, the light came on again and stayed on until I parked the bus at the storage lot and shut it down. Nothing we had running (either on generator or shore power while parked) seemed affected and we noticed no degradation in performance.

Yesterday, we went to the bus lot to replace the batteries in our WheelsTo-Go cart that rides in the front bay of the bus. While there, I cranked the bus and the House Battery Balance light was on again! (Note: We keep the bus plugged in to 50 amp power always when stored).

At the risk of confirming my ignorance yet again, I'll confess I have no idea what is causing this light to come on or what (if anything) I need to do about it. We rarely use the bus without either generator or shore power - at the most, on battery power for a few minutes at a time.

Can I get some advice and/or guidance from the POG braintrust?

[Jon Wehrenberg]

Michael,

That light is a chassis related indicator. There is nothing you were doing that I can see had any impact on that warning light.

For the benefit of those who might experience the same situation it is driven by a Vanner monitor which on my coach is located on the forward bulkhead above the chassis batteries. It is a box about 4" square with several wires attached to terminals across the bottom.

8297

You either have an issue with the Vanner Equalizer or the monitor is giving you bad information.

The easiest way for me to determine if it is the monitor is to check the voltage on the 12 and 24 volt inputs. If the equalizer is functioning as intended it maintains the 12 volt reading at 50% of the 24 volt reading within about 1/2 volt.

In other words, with the engine running the 12 volt reading might be 13.7 volts and the 24 volt reading might be 27.5 volts. The lower reading is within .1 volts of being exactly 50% so it is within range.

If your 12 volt readings are 1/2 of the 24 volt readings within 1/2 volt the monitor has likely failed. If they are out of range the equalizer may have failed or is about to fail. That can be checked by following the Vanner instructions found on line or in your operator's manual.

The purpose of the battery balance is because on the chassis the bus uses both 12 volts and 24 volts. The equalizer is set up to insure all four batteriies' voltages are being maintained even though the loads may be disportionate.

[Mark3101]

I had the same problem the day we got the bus. It was the equalizer, not the monitor, and Prevost Ft. Worth changed it out on the spot. They indicated that they were having issues with some of them, and we were in and out in about an hour. Technician checked the voltages as Jon indicated and went right to the parts guy and came back with a shiny new one in the box.

Haven't had an issue since.

[truk4u]

Michael,

If after you check the Equalizer like Jon said and find it's the Monitor, there's one on e-bay here:

http://cgi.ebay.com/ebaymotors/Vanner-Electrical-System-Monitor-EM70D-/140510030599#ht_1099wt_1161

Jon's is a 70A and this one is a 70D because Vanner keeps updating.

[Jon Wehrenberg]

My guess is the updates have been to improve reliability. A lot of the POG owners have replaced their monitors.

[michaeldterry]

Michael,

If after you check the Equalizer like Jon said and find it's the Monitor, there's one on e-bay here:

http://cgi.ebay.com/ebaymotors/Vanner-Electrical-System-Monitor-EM70D-/140510030599#ht_1099wt_1161

Jon's is a 70A and this one is a 70D because Vanner keeps updating.

Unfortunately, the guy who listed the Vanner EM70D on eBay sold out of them before I could check out the listing. I contacted him, but he doesn't have any more now. Thanks for the heads up anyway!

[Jon Wehrenberg]

Michael,

I lean towards the monitor being the problem, but before you purchase a new one it is worth checking to confirm it is bad. It could be a bad equalizer.

[Gary Carmichael]

Damn! you guys are good! So much knowledge Michael, we are blessed to have people with this info on POG but that's what it's all about.

[rfoster]

Gary: The early and old members of POG received the "Magic Decoder Ring" and membership card for their 50 bucks. Inflation has run the membership to a 100 bucks but no ring and no card.
Just good advice.

[JIM CHALOUPKA]

That ring is invaluable:

[Jon Wehrenberg]

Damn! you guys are good! So much knowledge Michael, we are blessed to have people with this info on POG but that's what it's all about.

Gary,

What you see as knowledge is not much more than a recollection of all the stuff that broke on our buses and the ability to relate that to somone else having the same problems. I wish we never had stuff break.

[Danss]

In 3 years I have had to replace the Vanner part 2 times to turn off balance light. Part must be made in bangladesh!

[truk4u]

Michael,

Did you stick a pin in my voo doo doll? My balance light is now on and my monitor has gone south. Maybe we can get a price break by buying two.

[michaeldterry]

Michael,

Did you stick a pin in my voo doo doll? My balance light is now on and my monitor has gone south. Maybe we can get a price break by buying two.

Tom - sorry if I jinxed you! I'm game to try for a volume discount if you can find a cooperative source! I'm going to need some instruction/guidance on specific steps to confirm the diagnosis of what's causing my balance light to stay on. I'm ( read Vita - hands) still trying to learn the fine points of troubleshooting electrical issues (like how to use an ohm meter, etc). :o

[Danss]

The best way to troubleshoot this problem is to buy the new Vanner part and if that does not correct the problem you can safely assume it is something else. That way you do not have to go thru all the agony of learning how to use an ohm meter and other tools. My bus has some pliers, screwdrivers and a hatchet, and if I can't fix it with those I am out of luck!

[merle&louise]

The best way to troubleshoot this problem is to buy the new Vanner part and if that does not correct the problem you can safely assume it is something else. That way you do not have to go thru all the agony of learning how to use an ohm meter and other tools. My bus has some pliers, screwdrivers and a hatchet, and if I can't fix it with those I am out of luck!

The hatchet works especially well on those pesky computer circuit boards!

[Jon Wehrenberg]

That's easy for Dan to say because his problem was solved by replacing the monitor. He used more than a hatchet to replace it BTW.

[truk4u]

Michael,

The Monitor can be had at Turbo Diesel in Atlanta, 800-241-4389, ask for Chip and the cost is 106.09. This is assuming it's the Monitor and not the Equalizer. If your stuck and can't get a meter on the Equalizer to verity it's good or bad, I'll be back home Friday and I should be able to get to Woodstock over the weekend.

[Jon Wehrenberg]

Michael,

If the coach flipper doesn't get to you fast enough send me an email and I will write up a how-to-do that even JDUB could follow.

[phorner]

Michael,

If the coach flipper doesn't get to you fast enough send me an email and I will write up a how-to-do that even JDUB could follow.

Now that was way harsh.....

[Jon Wehrenberg]

Paul,

Like he isn't way harsh when he criticizes our rolling bordellos.

[michaeldterry]

Michael,

The Monitor can be had at Turbo Diesel in Atlanta, 800-241-4389, ask for Chip and the cost is 106.09. This is assuming it's the Monitor and not the Equalizer. If your stuck and can't get a meter on the Equalizer to verity it's good or bad, I'll be back home Friday and I should be able to get to Woodstock over the weekend.

Tom - we would really appreciate it if you are willing to come guide us through troubleshooting this issue at your leisure on Saturday (we have a previous engagement on Sunday)! Or, if it's easier for you, we could arrange to run the bus up to Jasper Saturday.

[truk4u]

PM'd you Michael.

[flloyd]

I replaced my Vanner unit last year, having the same problems. Bought it from a place called Diesel Injection Service, somewhere in Wisconsin, I think.

The units aren't very sophisticated. Until the replacement arrived, I just unplugged the indicator light output. I had measured all the voltages with a voltmeter and everything was in spec, even though the light was lit.

[Mark3101]

So Michael, what did you find out??

[michaeldterry]

So Michael, what did you find out??

Mark - the oddest thing - Tom Chilcote (truk4u) came down Sunday before last and checked the readings with his meter (Unfortunately, Vita and I weren't able to be with him as we had a minor family crisis that came up suddenly and required our attention). I don't know exactly what all Tom did, but he confirmed that the actual readings were within prescribed tolerances, which indicates that we have a bad Vanner monitor. However, the strangest thing is that ever since Tom touched Evangeline, the battery balance light has not come back on! We just used the bus for a getaway to Paradise Valley in Dawsonville, GA this past weekend and the light did not come on once!

If/when the light does reappear, I plan to replace the Vanner monitor. Until then, I'll remain fat, dumb and happy - and thank Tom for laying his magic hands on the problem!

[Mark3101]

Don't you just hate intermittent problems? They can drive you nuts! Hope it doesn't come back on and that Tom's magic touch did the trick.

[Jon Wehrenberg]

There are only two ways I know to cure intermittent issues. The first uses a "scorched earth" approach in which anything that may even remotely suspected of being part of the problem is rebuilt or replaced.

Or there is the "fugetaboudit" approach in which you ignore it until whatever is breaking finally fails completely, at which time you just rebuild or replace the bad part.

Neither approach is really a good one.

[truk4u]

Hey Michael, now that was some good Ju Ju I put on your bus and I learned it from Jon!:p

[phorner]

Paul,

Like he isn't way harsh when he criticizes our rolling bordellos.

Since I only have a Liberty Lady Classic, and not an Elegant Lady, I can only rise to the level of rolling casino........

[Denny]

FWIW Vanner will rebuild the equalizer for less than half of a new one.

[chtree]

Guys we have just replaced our chassis batteries and the Lo bat light on dash still comes on once in awhile and doesn't go off until we plug in or start the generator. Any thoughts. Thanks. Chris

[Jon Wehrenberg]

Chris,

Your Lo Bat light is powered through the Vanner monitor. Check your voltages at the monitor to determine if the voltage is really low or the monitor has puked.

There was a recent thread on this topic.

[chtree]

Thank you Jon. Sorry I must have missed that prior thread. Chris