vehicle battery dead

[dvishny]

Hello all: 1997 Georgie Boy. Been sitting for 30 days plugged in, the vehicle battery (not coach battery) is deader than a doornail. no fuses blown, no circuits appear to be tripped. checked the power-it's getting power, lights work in the coach, the outlets inside do not work, the microwave is not getting power. any suggestions?
thanks,
Dan

 

[Carl L]

Well the Georgie Boy is 9 years old, how old is that chassis battery?  They last not much more that 5-7 years.  Microwaves operate on 120VAC, not 12VDC.  Inside lights work on the house batteries; outside on chassis battery unless you are talking about a patio light.

I would say, absent better information, that your chassis battery has died of old age.  Replace it and have the charging circuit checked.

 

[dvishny]

thanks Carl for the quick response- the battery was replaced 2 months ago. after better observation, i discovered that i actually was not getting power (my circuit inside my house was blown)- when i fixed that, it appears that the outlets inside the rv work. so, i'm pretty sure that i have fixed the problem- fingers are crossed. thanks again

 

[Gary RV_Wizard]

It's also possible that your chassis (engine starting) battery is not charged by the coach's charging system. Some RVs do not.

Now that you have power to the coach (and its charger), see if the batteries charge up again.

 

[Gary RV_Wizard]

I received this update from Dan...

Hi again- i can't seem to figure this one out. I have included the original post at the end of the email... i replaced the original chassis battery, i'm plugged into shore, now the new battery got drained. i dont know what could be draining the chassis battery, do you have any suggestions? i have not driven it since i replaced the battery.

help is much appreciated,
dan vishny

There are two separate issues here:
1) the chassis battery is not getting charged while the coach is plugged to shore power

(2) Something is draining the chassis battery in 30 days or less

#1 may be normal for this coach - in some older rigs the chassis battery is not charged from the house systems converter/charger.  I thought that by 1997 that most manufactrers were providing chassis battery charging, but it's a possibility to consider. Is this a new problem or has it always been that way?

Assuming you do have charging from the house system, it is also possible that there has been a failure in solenoid switch that connects the house system to the chassis battery when the engine is not running (the solenoid opens when the engine is started and the engine alternator takes over. The converter would be running but no power would reach the chassis battery. Can you identify where the converter output leads go off towards the chassis battery. Is there a 12V power control panel somewhere with fairly large wires leading off to the engine/chassis battery? Can you test this wire for continuity all the way to the chassis battery?

As for #2, it is not terribly unusual for coaches sitting idle to drain batteries, even the chassis battery, but sometimes there are extra, unnecessary drains that can be eliminated or moved to another power source. One possible culprit is the power operated door step. Many models have a light underneath to illuminate the step at night and it is easy for this light to be on but unnoticed in the daylight. Check it in the dark. Depending on what make and model step you have, there may be switch positions which enable the light whenever the step is out.  You may also have extra audio equipment that was wired to the chassis battery and draws a small amount of continuous power.  Alarms like CO and LPG detectors may also be powered from the chassis battery rather than the house batteries.

It's difficult to be very accurate in our suggestions without more info on just how the power systems in your coach are set up.  Is the converter/charger a separate box or integrated with the 120 VAC load center (breaker panel)?  If separate, where do the output leads go and are there seprate charging leads?  Is there a separate 12V power power control center somewhere, perhaps in a bay or adjacent to the batteries?  Is your chassis battery along side of the house batteries or up in the engine compartment?

 

[dvishny]

Thanks Gary:
To answer your questions- the converter/charger is a separate box, it is mounted in the bay where the electrical plugs into shore power. the output leads go from the converter to a 12v distribution panel (located next to it). there are wires leading out from the 12v dist panel (maybe going to the chassis battery?).? the chassis battery is under the hood.

my power operated doorstep has been down the entire time, however, i have never noticed a light- i looked everywhere and do not see a light.

I'm thinking that the problem is #2 not #1, since it was a brand new battery (2 weeks old to be exact). I think something is draining it, I just cant figure out what??

thanks again for your input

 

[Karl]

Start troubleshooting by looking in, on, around, and under the rig on a dark night. See if any lights are lit - even dimly. Check under the hood and inside any storage compartments. Failing that, make a test light. Take an ordinary automotive parking light bulb and solder one wire to the solder blob and another to the brass shell. Disconnect the ground lead from the battery and hook up the light between the now removed battery cable and the battery negative terminal. If the light lights, you're drawing current from somewhere. Start by removing one fuse at a time from the fuse block, mark where it came from, and see if the light went out. Continue doing so until you have found the one which is causing your problems. It may be MORE than one, so leave the fuse out that caused to light to go out, and start replacing the other fuses one at a time. Hopefully you will be able to replace all the rest of them without the light going back on. If not, leave the other offending fuse(s) out and continue replacing those still removed. This should narrow down your problem to a single circuit. Do this and get back to us with the results. Could be a defective switch, short in the wiring, stuck relay, etc. Without knowing which fuse it is, it's impossible to go any further. If by some slim chance you've removed all the fuses and the light is STILL on, you've almost surely got a problem in the chassis wiring, brake/hazard/head light circuit(s), or the alternator voltage regulator circuit.
Good Luck!

P.s. There may be more than one fuse block; one or more under the dash, one or more inside the engine compartment, and more in the DC distribution panel inside the rig. Check them all.

 

[Gary RV_Wizard]

I'm thinking that the problem is #2 not #1, since it was a brand new battery (2 weeks old to be exact). I think something is draining it, I just cant figure out what??

Dan,
You must have BOTH problems because if the charger is working and connected to the chassis battery, it would easily replenish any charge lost to whatever power drain in causing #2. So it definitely is not charging the chassis battery, either by defect or design.  I gather you do not know if the house system ever charged the chassis battery before. As I said earlier, it is possible that it does not.

If your step has a light, it is underneath the step housing, in the area where the step retracts. It's typically a small globe and not easy to see - it just provides a faint glow around the steps.

You need to get that battery charged up again and then see how long it takes to drain down. It also needs some charge to do the kind of testing that Karl described. Do you have an automative type battery charger? Or jumper cables so you can jump the chassis battery to the house batteries or some other charging source? You need a short term solution to the dead battery problem so you can use the coach - or at least start it up.

So you need to try to isolate where the power is going and secondarily investiagate why no charging is occurring (or verify that there is no auxiliary charging in the design of the electrical system). It might take a call to GBM to find out if the electrical system is supposed to be charging the chassis battery.

 

[Weewun]

My 2005 Diplomat did the same thing (dead in less than 2 months after purchase) .  I researched the wiring diagram and contacted Monaco and found that  the Chassis Batteries only charge from the engine and Generator.  I think that is poor design by Monaco, 'penny wise and pound foolish.'  I solved my problem by buying a $30 Battery Tender Junior which I plug in whenever I am going to be parked for over a week.

 

[Gary RV_Wizard]

My 2005 Diplomat did the same thing (dead in less than 2 months after purchase) .  I researched the wiring diagram and contacted Monaco and found that  the Chassis Batteries only charge from the engine and Generator.

Weewun,
I amazed that your chassis batteries charge from the genset but not shore power. The genset powers the entire coach's 120VAC electrical system and therefore the inverter/charger, just like shore power. They would have to go out of their way to design it so that the genset charges but not shore power.  We have quite a few Monaco owners here - can anyone else comment on this?  I'm curious... there is always something new to learn about these rigs!

 

[dvishny]

Well... I'm happy to report that  another problem has been solved from the rv forum community!

The chassis battery is not charged by the house system/shore power... only by the alternator when the engine is running...

as it turns out, there is a light underneath my step, which must have been on and draining the battery....

There is a battery disconnect on the chassis battery, probably put there beacause of the same problem that I had- I''ll either use that when we are sitting for an extended time period or purchase a battery tender as suggested..

thanks to everyone for the comments/suggestions/help, fingers are crossed that the problem is solved.

dan

 

[John From Detroit]

You may wish to consider some means for charging the chassis battery when plugged in to shore power.

Even if it's only a battery minder type charger (Very slow charger)

 

[RvMan56]

Gary,
  My 1999 Tropical from National doesn't charge the 12v engine battery either, it has gone dead before, so I use a small jumper wire a few days before I move to charge it up, I move every 2 to 3 weeks to dump anyway.

Kelly