Dead Battery Overnight

[sdunn4]

We are (hopefully) leaving tomorrow morning from northern New York, heading south for a couple weeks in our 2015 Roadtrek SS Agile. As it has been down to 0 degrees or less for the past few nights we planned ahead and added diesel fuel treatment to our fuel tank several days ago, and yesterday we took a trip out to make sure everything was working as it should, adding air to the tires as well. Everything ran fine and I stowed the charging cable (had been on shore power the past few weeks, as in the winter the solar panels frequently are snow-covered). Unfortunately I left the coach battery disconnect on. This morning the Sprinter engine will not even try to start. I hooked back up to shore power and very quickly I was back up to 100% battery on my coach indicator panel; but no luck starting the van. I tried putting a trickle charge on the battery under the hood but that did not help either. Several questions which may show my ignorance-
1) will having the coach disconnect on in cold weather kill the battery overnight? Nothing was left turned on.
2) if I inadvertently killed the Sprinter battery, is it as simple as jump-starting the van? If so, anything to watch out for?
3) any other suggestions or thoughts are appreciated; my last resort is to call AAA.

Thanks,

Steve

[markopolo]

Is the Sprinter engine battery under the hood? I recall them being under a seat but maybe it was a different model year .........

[SteveJ]

The quick return to 100% is interesting. Have the battery cables been cleaned lately?

Just looking at them will not indicate a bad connection. Try loosening the cables slightly and give them a bit of a twist and see if that does it, otherwise take them off, negative first, clean them with a wire brush or something abrasive, and reassemble positive first.

You could very well have a bad battery and it is 3-4 years old. Having taken it down to dead at this stage of it's life would definitely tilt toward replacing it. Being that age, I wouldn't even bother with a load test unless I had easy access a tester, which I don't. If you want, you could pull the battery, charge it, and then take it to an auto parts store to get load tested. Like I said, the age of the battery would have dictated replacement for me. Having a battery go down in the middle of nowhere pretty well sucks.

Just jumping it will not fix a bad battery.

Bummer on the rough start to your trip.

BTW, it was 78* at my house.

[sdunn4]

Thanks! The battery cables were loose- just loosened them and snugged them back up good and tight and the engine started right away; your input was very much appreciated! Sometimes it is the simplest details and of course I always jump to the worst case.

Steve

[Yoshimura]

For your information, most RVs have a battery separator that only connect both batteries (coach and chassis) together when at least one is recharging. Otherwise, both batteries (and systems) are not connected to each other. Thus you can't depleted the chassis battery by using the coach accessories.

We are also heading south but next week and from Montreal. Have a nice trip!

[SteveJ]

Awesome. Now get out of the tundra. Coming to Flowriduh?

BTW, next oil change do consider doing a proper clean up on those battery terminals.

[OregonTrader]

We also have a 2015 SS Agile. The batteries under the hood are for the coach. The chassis battery (for the engine) is under the driver floorboard. Under the hood, there is a terminal so that you can charge or jump the chassis battery. It's left of center above the engine; and has a red plastic protector on it, which you push in while turning to reveal the terminal. I leave a trickle charger on there in the winter.

[Rockwood27]

My guess is that your battery was not at full charge, after a short charge cycle. If you still had your RV plugged in and checked the battery condition idiot lights, then you were seeing the charger output. Unplug your RV and let it rest. Check the battery voltage with a volt meter at the battery. A fully charged lead based battery will measure about 12.6 to 12.7 volts. A half charged battery is about 12.1 volts. You shouldn't let your batteries get below this value or their longevity will suffer.

[sdunn4]

Thanks for the replies! No issues since we left home on the 14th of January. We’ve driven over 2,000 miles since then; in Key West now. Once we’re home in subzero temperatures, I’ll know for sure if the issues persist.

Steve