Battery meter on dash fluctuates

[tmmar]

I noticed the other day when I start the coach after it has been parked for a few days that the battery meter fluctuates from about the 12v area to the 14v area. The needle moves back and forth about 12 times and then it stops and settles in at just over the 13v line. Anyone else notice this happening? Not sure what is happening.
Thanks for any suggestions.
Tom

[JTN8]

Mine does the same thing... Then settles out and doesn't do it anymore. Seems like the alternator is cycling on and off when the coach firsts starts up and then it's good.

[Campin Cajun]

Mine does the same and if I am parked for more than 3 weeks it will give me the low battery warning also. After a few minutes of running the warning goes away.

[tmmar]

JT-
I thought the same thing, that it could be the alternator cycling or I also thought that it could be electrical components coming on line, one after another.
Hopefully it won't turn out to be a problem later on.
thanks,
Tom

[JTN8]

Originally Posted by tmmar

JT-
I thought the same thing, that it could be the alternator cycling or I also thought that it could be electrical components coming on line, one after another.
Hopefully it won't turn out to be a problem later on.
thanks,
Tom

Probably makes more sense that the components are
Coming on line. I agree, hopefully this is just normal and won't be an issue later.

[OldCoot]

Would believe it's the voltage regulator adjusting the current going into the battery.

[beipers]

How cold was it? Did manifold heater light show while you were cranking the engine? If so, the voltage level will fluctuate as the Cummins Engine ECU cycles the heater directly after start up.

[Mmnsc]

Tom
Freightliner told me it was normal as the system needed to warm and draws current as it cycles. Made me nervous at first. I hope you had a nice warm day.

[tmmar]

Marty,
Thanks for the info. Yes, temp in 70's and sunny. Hope you don't get hit too badly with the storm. Keep us informed.
Tom

[Jersey Guy]

This must be a Cummins thing, my Berk does it as well as my Dodge p/u with the 5.9.

[gasman94]

Ditto....Glad to hear that others have the same issue. Lights dim with voltage drop. Equalizes after a couple of minutes. I do keep my batteries charged with battery tenders.

[JTN8]

Originally Posted by gasman94

Ditto....Glad to hear that others have the same issue. Lights dim with voltage drop. Equalizes after a couple of minutes. I do keep my batteries charged with battery tenders.

Gas man, just wondering why you use a battery tender? I had an issue with my chassis batteries dying after a few weeks if sitting and when I spoke with forest river, they told me that the magnum inv/charger charges both your house batteries and chassis batteries. There is a solenoid that switches the charger from your house batteries to your chassis batteries once the house are full. Mine was not connected properly when installed so it was fixed. Not sure of your year or set up, but you may want to look into that.

[gasman94]

JTN8. Thanks. I've got '14. I know about using the inverter, but figure that the less time used on coach systems, the longer it will last. Bad part is that I am using 2 tender jrs. and 4 tenders. They do work well, though.

[JTN8]

Originally Posted by gasman94

JTN8. Thanks. I've got '14. I know about using the inverter, but figure that the less time used on coach systems, the longer it will last. Bad part is that I am using 2 tender jrs. and 4 tenders. They do work well, though.

They do work we'll!! Mine is a 14 too but when the chassis batteries weren't charging off the inverter/charger, I was using a tender plus, worked great but if I wasn't using it my chassis batteries would be low after about three weeks!!!