Battery goes dead

[jonalan]

I have a 2003 Ittasca Horizon. The start battery goes dead within a day of charging it an hooking up to motorhome. I can charge the batteries up but leave them unhooked from motor home for 5 days and they don't go dead. would appreciate any suggestions on where to even start checking.

[Skip426]

Welcome to iRV2.

Sorry your first post is about problems .

There are parasitic draws on the chassis battery , engine and transmission controllers and dash radio memory , but they should take weeks to run the battery down .

What chassis is your coach built on ? Freightliner ?
Caterpillar engine ?
Your charging the battery (ies ) but have you had them load tested ?
Start batteries don't tolerate being run dead even a couple of times .
Without load testing you don't know if the battery is properly charged and in good condition.

[twinboat]

Leaving them for 5 days unhooked is not much of a conformation of good batteries.
Maybe get them tested.

Yes there are parasitic draws on all vehicles now days but a good battery can last a few weeks and still start the engine.

[Biljol]

Get a good multimeter and when you hook up the battery place it between the negative cable and the negative post do not connect the cable and the post, this will give you the current draw on the battery.

That will start the adventure of bad battery or something is pulling to much power.

[Mark_K5LXP]

Should the battery test good, then it comes down to putting a ammeter in series with the cable, and measuring the draw. "Typical" will be something less than 100mA, anything north of that something is "on". From there you start removing fuses from the fuse block(s) one at a time to see what circuit has the offending device. It might be more than one, i.e. pulling a given fuse reduces the draw but doesn't eliminate it, so you chase them one at a time until the parasitic draw is normal.

Mark B.
Albuquerque, NM

[Demon13]

Originally Posted by jonalan

I have a 2003 Ittasca Horizon. The start battery goes dead within a day of charging it an hooking up to motorhome. I can charge the batteries up but leave them unhooked from motor home for 5 days and they don't go dead. would appreciate any suggestions on where to even start checking.

Check "output" on alternator also .. when it drops around 60% output this can appear as a "parasitic" draw..judging by age of your Coach..

[TonyMac]

My cargo compartment lights will kill my chassis battery really quick. On my rig, they light don't come on when you open the door, like a fridge, except the wet bay. There is a switch in the stairwell to turn them all on. If that switch is on, you don't notice it during the day, and I rarely get in the compartments at night, so those 9 lights will suck the batteries. A crappy rv dealer mechanic I fired turned them on on several occasions, as they entered the coach and hit switches until the inside lights came on. Morons didn't think to reset the switches that didn't perform the desired functions.

Then there's the wet bay. It has a plunger switch that turns on the compartment light when you open the door. If your rig has some of these plunger switches, make sure they turn off the lights when the door is closed. They can get out of rig.