Community Forums

seadaddler · 03-09-2018, 06:20 AM

Some MH when plugged into shore power do not charge chassis battery and only house battery and chassis battery only charges when engine is running and so when MH is just sitting the chassis battery may be used for memory to some part of engine like computer and radio or something.
Try running motor charge up battery and some way disconnect chassis battery
and see what happens and if that is what happens than put a battery discount
On the terminal.
Or have advance auto do a load test before wasting money on new battery and than find out the new battery is being drained and really need a shutoff chassis
switch.
Nick

brokenrule · 03-09-2018, 08:05 PM

I also agree with OldToolMaker. Shorted or dead cell will drain the battery quickly. His steps are solid.

To find a drain, remove the negative cable, hook a test light between the negative battery post and the cable. If the light comes on then there is a drain (which could be the computer or radio) and removing and replacing the fuses one at a time until the light goes out will show the draw.

I had an old Trans Am that had a car radio drain that would kill the battery in two weeks so I removed the neg term while it sat.

My current motorhome starting battery will get low after 6-7 weeks so I put a battery tender 10w solar charger on it and no more problems.

Forkyfork · 03-09-2018, 09:05 PM

Quote:

Originally Posted by cteat149

I do have one on there. I assumed being plugged into shore would charge that battery along with the house batteries. (I guess not) so I kept it engaged.

If you have a cutoff directly on the hot terminal on your engine battery and the battery is dying after fully charging then your battery is toast. The "salesman switch" is only a partial cut off of your house batteries not your engine battery.

If your battery is dead and you are expecting the alternator to charge it back up, you have a lot of driving to do, plus its bad for your alternator. I picked up a pretty good charger that will do a higher amp charge and then trickle charge after. Don't skimp on chargers. My husband bought a cheap charger and stuck it on a bad battery and caused the acid to boil.

A good charger would have caught the issue with the battery and shut of. All chargers when charging questionable batteries need to be checked often.

Its pretty common among MH manufacturers that the engine battery doesn't charge with the house batteries.

My engine battery only charges from the alternator. My house batteries get charged from everything including the little solar panel on the top.
My engine battery runs the steps and the levelers. If I'm in and out a lot or move the slides I have to be careful to plug in the charger to bring the batteries back up.

There are normal draws off the engine battery. Even sitting a good battery will drop below a safe level within a short time especially if its cold.