Chassis battery

[Barbaramhicks]

Our Chassis battery loses voltage while we are camping. It's been in shop many times. Thought it was fixed. After 5 days we had to use battery booster and let it run for awhile. Any ideas why this keeps happening?
Newmar Bay Star 2020.

 

[Old Bubblehead]

a bit more detail on your rig and situation might help folks help you. Most rigs have some type of relay that shifts charging between chassis and house batteries. It usually shifts on battery condition. Many times these get rusty and are not able to shift so the load not getting routine charging depletes.

 

[TJ&LadyDi]

How old is the chassis battery and has it been properly load-tested (not just an at-rest voltage check) when it was “in the shop.” Sadly, a lot of “shop mechanics” don’t know how to load-test a battery.

Your issue sounds a lot like a failing battery, but could also be the charging circuit as noted by others. Information on the year/make/model of your RV would certainly help us in making a more informed assessment of the problem.

TJ

 

[Barbaramhicks]

How old is the chassis battery and has it been properly load-tested (not just an at-rest voltage check) when it was “in the shop.” Sadly, a lot of “shop mechanics” don’t know how to load-test a battery.

Your issue sounds a lot like a failing battery, but could also be the charging circuit as noted by others. Information on the year/make/model of your RV would certainly help us in making a more informed assessment of the problem.

TJ

Newmar Bay Star 2020 bought new

 

[Joe Hogan]

Sounds like a B.I.R.D issue

 

[Barbaramhicks]

Sounds like a B.I.R.D issue

Been replaced!

 

[Neal]

When plugged in to shore power the chassis batteries should be getting maintained. On some coaches such as mine there is also a small solar panel on the roof Newmar installed to help charge the chassis batteries. I'm not sure if you have one or if it's working. I suggest putting in a call to Newmar and see what they say and if you're still under warranty they may set you up to take it somewhere near your location.

 

[Joe Hogan]

This document gives a good description of the charging system in a Baystar starting in chapter 6

https://newpar.newmarcorp.com/instance1Env99NEWMAR/html/images/2017BSCAOG.pdf

 

[Barbaramhicks]

Thank you. It's been in shop more than we've had it. We can use it for 4-5 days before we have to start it and charge it. 4-5 days is good. We used to have to do it every 24! Crazy. Love the coach when it starts! Really thought it was fixed. But guess not!

 

[TJ&LadyDi]

Despite the fact that the battery is only a couple of years old, I would have it load-tested. Brand new batteries have been known to fail.

TJ

 

[Joe Hogan]

To fix this you are going to have to get your hands dirty.
You will have to test each leg of the electrical system for errors.
You should start from a known state.
Load testing the chassis battery is a good start.

Unplug from shore power and turn off all electrical draws.

Then start a check for fantom draws on the chassis battery.

Then check continuity between BIM and chassis battery. Also check continuity between house batteries and BIM.

Then record the voltages of all batteries and plug the RV into known good shore power.

Verify inverter:/ charger is active via the inverter controller.

Check voltage of chassis battery and house battery. If voltage has increased at battery the charger is suppling power. This will point out faults.

Check voltage of House battery lead at BIM and Chassis battery lead at BIM.

This will show where voltage is going and not.

this will help you diagnose what might be the issue.

the fantom draw test will show hidden users of power.

we had unknowingly turned on an outside tv with a remote control.
Took a while to find that one.
Also once left a basement light on with a closed cabinet.
Hard to diagnose when you are distracted with all the potential issues.

 

[Joe Hogan]

 

[Joe Hogan]

Also does the Baystar have the standard 45 Amp Converter or optional Inverter?

 

[Rjs]

Newmar Bay Star 2020 bought new

I am having the same problem in my Thor ACE that my house and chassis batteries go dead even plugged into shore power.

 

[AbdRahim]

I am having the same problem in my Thor ACE that my house and chassis batteries go dead even plugged into shore power.

Sounds like your inverter/chager is not working