eng battery dead

Topic: eng battery dead (Read 2478 times) previous topic - next topic

eng battery dead

February 28, 2019, 08:23:14 am

Have 96 U320 ,just returned from 6000mile trip no issues, due to flooding couldn't bring my home.Parked mh unconnected to shore power. Left frig on, nothing else. Next day no start, voltage read 10. Jump started, center shows 12-13. Shut off frig, next day no start. Started gen boost on ran 30min. Next day no start, started gen, after 10min started eng, meter reading 13.5. Got MH home pulled 3 eng batteries (5month old) had tested @ O'Reilly and then auto zone all test good. Installed batteries, started volt read 12-13.5. Turn off inverter,house breakers and 12v system disconnect.This morning started right up. Still havent connected to shore. Not sure what to ts next, but beleive it has to be something to do with inverters. I have spent hours on forum reading about similar problems,as always learned alot,can't find what relates to this issue . On a side note this is my first post. Thank you

Re: eng battery dead

Reply #1 – February 28, 2019, 08:40:24 am

The inverter takes some power from the batteries (called "stand-by", even if no 120 VAC items are on.

And, there may be some things on such as memory for TV, etc.

So, when no shore power, and you don't need to run appliances on the inverter-powered sub-panel, turn inverter OFF.

You could also have a parasitic draw on the 12 VDC side of things-- something like a light in a basement bay. Here, an ammeter is your friend. Pull fuses to identify the source of the draw.

Re: eng battery dead

Reply #2 – February 28, 2019, 09:32:07 am

Quote from: Phil 1:3 – February 28, 2019, 08:23:14 am

Have 96 U320 ,just returned from 6000mile trip no issues, due to flooding couldn't bring my home. Parked mh unconnected to shore power. Left frig on, nothing else. Next day no start, voltage read 10.

If you made the 6K mile trip with no issues, then your alternator and battery isolator are probably working fine. Your batteries should have been fully charged when you got off the road and parked. The next day the engine start battery is dead. Nothing on overnight except fridge...

What kind of fridge? Residential, or original electric/propane model? Regardless, the fridge should not drain the start (chassis) battery - it should draw off the coach (house) batteries (either directly or via inverter). Unless the BOOST switch was on...

As Brett says, there must be some kind of substantial parasitic drain on your start battery to kill it overnight.

"voltage read 10" Where are you reading the battery voltages - on the dash volt meter, or at the batteries using a multimeter?

Re: eng battery dead

Reply #3 – February 28, 2019, 10:03:04 am

Disconnect the engine batts and see what still works. Something is wired to the wrong source. Is this a new thing? What is the back ground history?
Is the fridga resi Electric? Etc.

Re: eng battery dead

Reply #4 – February 28, 2019, 10:41:13 am

Headlights on?

Re: eng battery dead

Reply #5 – February 28, 2019, 11:28:46 am

Like Bob said, I once left the headlights on. Bright sunshine so I didn't notice. Had to start the generator and tun through the boost switch to start the engine. I was chasing down the problem when the wife asked why I had the lights on in the middle of the day sitting in the campsite

Yes, she still reminds me, from time to time.
Larry

Re: eng battery dead

Reply #6 – February 28, 2019, 12:20:20 pm

Killed a new set of spiral wounds leaving the headlights on. Once.

The auto combiner would help as if any charging had occurred from whatever source the combiner would tie the batteries together as long as the draw did not exceed the charging input.

A voltage lower than charging voltages disconnects the combiner.

Might help save a battery bank.

If normal AGM's are discharged heavily that can reduce the power and/or cycle life.

A desulfurizator could restore their capacity. Slow improvement but works.

Re: eng battery dead

Reply #7 – February 28, 2019, 01:03:15 pm

What Wolfe said. Inverters should be turned off when not in use. My start battery (unknown age) had a bad cell a couple years ago and read 10.3 volts. Wouldn't charge any higher.

Re: eng battery dead

Reply #8 – February 28, 2019, 01:23:20 pm

Did the refrigerator run on 12 volts or propane? If 12 volts it may have drained the batteries and you did not run the engine enough to recharge them fully. But then the engine battery should not be wired to anything but the starter, maybe a under hood light left on?

Re: eng battery dead update

Reply #9 – February 28, 2019, 02:12:51 pm

Let me start my saying you guys are awesome wasn't expecting all this attention, thank you, even Wolf posted, I appreciate all the wisdom out there. Here's where things are. I had then interface turned off. I went started again,shut down turned on interface and have a overload light flashing. Cycled through a few as still flashing. Both breakers off and 12v off. Still not connected to shore. I did connect sp heard thump,interface still flashing. Now this may be vital information, we left AZ for return hm TENN, I was going to check coach batteries (fill 2 mos prior) and door no open. As you know would require gas tanked removed, and cut thru stainless to pull cables. This was going to be my 2nd post (How do I open battery compartment door when latch won't work?)
M. Johnson
USMC & Sheriff Deputy Ret

Re: eng battery dead

Reply #10 – February 28, 2019, 02:38:34 pm

And the frig is Samsung

Re: eng battery dead

Reply #11 – February 28, 2019, 04:22:30 pm

Quote from: Phil 1:3 – February 28, 2019, 02:38:34 pm

And the frig is Samsung

Bingo! But doesn't it run off the house batteries? Of course if you had your boost switch on it would have drained both the house and starting batteries.

Re: eng battery dead

Reply #12 – March 01, 2019, 09:40:18 am

Push in on the bottom of the door and jiggle the bottom of the door as you release the handle. If that does not work, if you look from underneath, you will be able to release.

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eng battery dead

February 28, 2019, 08:23:14 am

Re: eng battery dead

Reply #1 – February 28, 2019, 08:40:24 am

Re: eng battery dead

Reply #2 – February 28, 2019, 09:32:07 am

Re: eng battery dead

Reply #3 – February 28, 2019, 10:03:04 am

Re: eng battery dead

Reply #4 – February 28, 2019, 10:41:13 am

Re: eng battery dead

Reply #5 – February 28, 2019, 11:28:46 am

Re: eng battery dead

Reply #6 – February 28, 2019, 12:20:20 pm

Re: eng battery dead

Reply #7 – February 28, 2019, 01:03:15 pm

Re: eng battery dead

Reply #8 – February 28, 2019, 01:23:20 pm

Re: eng battery dead update

Reply #9 – February 28, 2019, 02:12:51 pm

Re: eng battery dead

Reply #10 – February 28, 2019, 02:38:34 pm

Re: eng battery dead

Reply #11 – February 28, 2019, 04:22:30 pm

Re: eng battery dead

Reply #12 – March 01, 2019, 09:40:18 am

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