dead batteries

[juan]

I just went out to start my motor home and everthing was dead.
When I turned the key nothing was there. Nothing in the coach area either. So I hooked her up to 110 ac and after about 15 minutes I got enough juice to fire the engine from the coach battery.

The only thing I could find that was left on was the gas detector. I wouldn't think that would run everything down in four weeks. Nothing in the coach is supposed to run the engine battery down is it?

JR

[djqualls]

What coach do you have?

I just had the same problem while connected to shore power all the time. Engine battery was dead, but house battery had power but weak and ran down before I could get it started.
I had to fire up the genset to get it to charge and start. Not sure why the genset charged it when it was coinnected to shore power all the time maybe was just a coincidence. I'm confusing myself while writing this post as to what my problem may be..........


Check my recent post in Mystery cable thread....

[earljan34]

Hey guys I had the same problem in every MH I have owned. Here in NE it gets cold and we don't always start it for a month or so, I installed a Battery Minder in the MH and have not had a dead Battery since, This unit has a Charge Wizard on the Converter/Charger that won't over charge the house Batteries same as the Battery Minder does on coach Battery.

Earl

[RJ82much]

Ah, here we are with the good-ole' dead-battery syndrome. First, a little canned blurb I posted a little while back:

>>>>>>>>>>>>>>>>>>>>>>
Our 8351 chassis battery discharged like yours. With hindsight, it seemed to occur at shorter & shorter intervals of nonuse. My dealership service department "investigated" several times to find "nothing wrong"; scolded me for mistreating the battery (typical answer for everything). With a lot of noise from me (squeeky wheel) & words of wisdom from the factory, the battery was determined to be defective & replaced on warantee (with a cheap brand, of course).

Think about this: The chassis is 1 year older than your model year RV built on it. A case could be made that the battery has sat activated, discharged, outdoors (perhaps frozen), for up to 2 years before you took delivery. A defective battery is not surprising.

I HAVE learned to hit the disconnects when our coach is going to sit for any time & have never had the discharged problem since. Do remember, that if you discharge your chassis (engine) battery, calmly start your generator (It uses the coach or house batteries). It will charge your dead engine battery thru the "Intellitec IRD Relay", albeit slowly. I think you have to depress the "Auxiliary Start Switch" on the dashboard (picture of a battery). You may be able to start the engine off the house batteries without the generator using this switch, but if you run those down, that's it. Start your generator first, then the engine. The engine alternator will provide a rapid recharge to the engine battery.
>>>>>>>>>>>>>>>>>>

I left my shore power connected with the disconnects "on" last year - forgot about them. I don't have any special battery-charge control in my unit. The house batteries hadn't lost any water by spring time, but I don't think this is a wise practice unless you have equipment like Earl. The safest practice is to open your disconnects. Plan to start the generator & gas engine at regular intervals throughout the winter. I let both run until the coach interior has fully warmed. That seems to be a pretty good timer, though perhaps a waste of propane. I fight the urge to turn on any of the electronics (TVs, entertainment center) because I don't feel comfortable starting them from near-zero temperature conditions (Western NE - often verrrrry cold).

What's the recommendation for deisels?

[earljan34]

Hey Bob, Just curious what the temp. is out your way? Here in RI we are at 12 deg with 25-30 mph winds right now guess wind chill is about 0. :roll: I am sitting in front of the Fire Place with a nice warm fire going, The advantage of the laptop. :)

Earl

[RJ82much]

Hi Earl,

It was a tad under 0 degrees (actual temp) this AM when I left for work -Not that windy. I am so used to cold weather that I didn't really give it (much of) a thought. We only have about 6 inches of snow on the ground. I tried snowmobiling around property yesterday, but there is no protection from rocks & downed trees - not any fun.

Our coal stove keeps our house reletively comfy, but electric baseboard backup is doing it's share also... I'm letting the MH stay stone-cold, probably better than stressing thru warming & cooling cycles. Once the temp breaks, & the sun gets to shining on it, I'll start it up for a good warm-up cycle.

Wireless or modem internet connection with the laptop? I bought a Delorme GPS transponder + Streets software & Topo USA software to use thru my laptop in the MH. Can't wait to try it

[earljan34]

Bob, I have the Co-Pilot live #9 Navigation system on the laptop also the Trailer life one that covers RV Parks, and on old version of Streets & Trips. They all work fine but the Co-Pilot has a RV height warning but they are only a guide you can confuse them! :?

Earl

[juan]

I have a 29' Cavalier Class C. We are in AZ however it has been unusually cold, we actually lost shrubs to frost this year. I thought maybe something in the coach was runing the battery down. But the chassis battery should not be affected by that?

Prior to the recent purchase of this motor home we had been doing the TT thing so I know that deap cell's go down just sitting. But I had no idea the chassis battery would go down so fast without a draw (I'm assuming now that there is no draw).

It may just be timing...the chassis battery may just be old although it looks new. There is no indicator of date of purchase on it and it is a Ford battery so it might just be original. It took all day to charge at 20 amps.
I'll keep an eye on it.

Meanwhile I'll leave the coach plugged in. Thanks everyone!

jr

[RJ82much]

Actually Juan, the problem maybe was that you left it plugged in. Our standard converters don't have the specialized circuitry that control the charge (other than trickle charge) & don't excercise the battery like top-end DP coaches are likely to have. You may have boiled water out of your battery limiting the amount of charge they'll accept.

If you leave your diconnects on, without shore power, your TV antenna amplifier may be on, CO2 detector, light in the disconnect switch could all contribute to small drain. Think of it this way, suppose there is 1/4 amp draw... that would be 6 amp-hr per day or 42 amp-hr per week. In 3 weeks, you have a dead or very weak battery.

It's sort of lose-lose.

[juan]

I charged the chassis battery and put it back in. I hooked up the positive first then the negative. When hooking up the negative there was a pretty good spark. That generally means that there is a draw. I can't find anything on.

I read many posts from people who leave their motor homes plugged into shore power when not in use. As of today I've started this myself. Should I not do this?

BTW the only thing that I can find that stays on is the C02 detector. The tv amp is off & there is no light on my disconnect switch. There is a light on the emergency start switch but it goes out when that switch is off, which it is.

I'm sure that there are other things that draw in a motorhome like this, there are so many electronic items in the coach and in the engine compartment. I just find it hard to believe that the chassis battery should drain in 1 month under normal conditions. That just doesn't sound right.

thanks for your help and suggestions.

jr

[earljan34]

juan, To eliminate this problem install a battery minder on the chassis battery, Just sitting there with the batt. connected it will drain even my other toad did the same thing if I left it for a month with out starting it as the alarm and other electronics draw. I have had no problems since installing the battery minder and the charge wizard in the MH. Small investment for knowing it is ready to go when you are No Surprises. My coach came with Inteli-Power converter/charger and I added the charge wizard for $25. the batt minder is about $45. not a big investment for peace of mind.

Earl

[RJ82much]

Juan, once again I believe that I am my own worst enemy - my confusion whether "chassis" means engine or house.

It is your engine battery running down, correct? (I originally assumed house battery)

If so, the converter & perpetual shore power play no part in the state of the engine battery (unless there are modifications). The engine battery is completely separate from the "house". A common misconception is that turning off the ignition disconnects all power draw from the battery. It doesn't. Just like in your car, radio circuits remain energized to memorize your station settings & the clock. The computers (ECMs) that control every aspect of your engine remain powered. They have to remember the tuning settings. The security system remains active. Etc etc. Think of what you go thru when you change the battery in your car, how you need to reset your stations, how you are told to drive some number of miles so that the computer can retune your car.

When the garage mechanic says there is "no load" on your battery, often he's looking at his "multimeter" for 1 or 2 amps flowing. He might not even notice a 1/4 amp (250 milliamp) or less draw. It is my understanding that a typical truck or auto battery might be rated 75 to 125 amp-hours. That was the basis for my prediction of 1-month. (4 weeks = 672 hours) A "trickle discharge" from the above devices could easily drain away 170 amp-hr capacity from the engine battery in a month.

Again, you need to kill the disconnects, or install a charger on the engine battery, either via a device as Earl mentioned or even a simple battery trickle charger under the hood, turned on for a day or 2 every month.


Hopefully, I did not overstate my case too much... thanks all