Chassis Battery Charging on a Berk 360QS

[JohnKen]

How are the chassis batteries charged on a 2008 Berk 360QS? I received a 'system voltage low' warning today on my driver's console. When I checked the chassis batteries, they were at 12.3 volts. I'm charing them now with an external charger, but since I'm getting ready to hit the road on an extended trip, this is a bit worrisome. Suggestions/guidance greatly appreciated.

[Chrisbrock]

Shore power ?

[JohnKen]

Originally Posted by Chrisbrock

Shore power ?

Well, that's what I hoped, but apparently not. Motorhome was in the shop for a week and was plugged in to shore power for at least the last day or two. Then 1 hour drive home. Problem occurred the following day.

[Chrisbrock]

Sounds like a problem in the charging system. I would start there.

[AREA51]

JohnKen,
My 2008 360QS charges the house batterys when the engine is running and when when the genset is running. Also when plugged into shore power. Sometimes when I light off the coach I get the "system low voltage" with a voltage reading warning, but it shortly goes away. If you check the three 12V power outlets, you will see that one of them is tied to the house batteries and is always powered up as long as you have the 12V switch on by the front door. I usually carry on of those little LCD volt meters that plugs into the 12V outlet, with that you can see which is powered up with the ignition off. It also gives the voltage so you can see when everything kicks in and the voltage increases.
GOOD LUCK
AREA51

[boowho]

Originally Posted by JohnKen

How are the chassis batteries charged on a 2008 Berk 360QS? I received a 'system voltage low' warning today on my driver's console. When I checked the chassis batteries, they were at 12.3 volts. I'm charing them now with an external charger, but since I'm getting ready to hit the road on an extended trip, this is a bit worrisome. Suggestions/guidance greatly appreciated.

I get that same warning all the time on my '11.

Yet the engine always cranks in a "lively" manner; never sluggish.

I may get a nasty surprise someday, but for now I've dismissed it as a false alarm.

Boowho??

[JohnKen]

Thanks for the tip, Area51. Hadn't thought about the accessory plug for easy access for voltage check . Now I've just got to find my digital meter. Still trying to get organized for full-timing. BooWho??: engine cranked fine on my rig as well, but after a short period of idle, an 'auto idle' function kicked up the RPMs. I was outside the coach and thought the DW had her foot on the accelerator! Charged the batteries with an external charger last night, so perhaps, that's all that's needed. Guess time will tell...

[Edward972]

Have the same coach, got the same message. It would go away but return on start up. Replaced the start batteries and it went away. Apparently it senses bad batteries.

[Phil57]

I would think if the voltage dropped to 12 v and it hasn't sat for awhile the batteries are bad. I would have someone check them or it cause the alternator to fail also.

[JohnKen]

Batteries are nearly new. Interstate 'no maintenance' installed by previous owner in March this year. Charged them overnight last night and they seem to be holding a charge OK. I'll definitely be keeping an eye on them and will load test them at my earliest opportunity. Also wondering if low voltage might have caused the Water In Fuel warning that has periodically popped up. Each time I checked, I could not detect any moisture in the fuel I drained. Just another of life's great mysteries to ponder...

[ernest917]

I had the "water in fuel" warning and it turned out to be a bad sensor.... Replaced it and problem solved .....

[beipers]

The low voltage warning at start up is normal for a Freightliner with a Cummins when the weather turns cold. If you read the operators manual section on starting the engine when cold, it has a note regarding this. It has something to do with how the manifold heater works. I'm not sure at what temperature this kicks in, but it doesn't need to be very cold for me to see it.

[Hallen01]

While out at FR Berkshire Diesel Division recently, I had a chance to talk with the technician who installs, and is expert on all the electrical systems.

He stated that while the MH is being driven, the chassis batteries are charged first, then when they are done, the house batteries are charged. While parked, the situation is reversed. If the switch on the console for altrernate startup (from house batteries) is held down, the situation is reversed.

Remember that when hooked up to shore power to recharge or trickle charge the house batteries, you must have both the battery disconnect switch (located near the floor next to the entrance door) and the house batteries isolation switch (in the compartment with the four house batteries) in the "on" position. The inside switch isolates most of the coach systems from the batteries, and the outside switch isolates the house batteries from everything external to the batteries, including the Magnum charging system.

Also remember that when on extended trickle charging (I'm hooked up to shore power year round, when not away on a trip), you are making hydrogen in the batteries, so you need to add distilled water up to the bottom of the fill rings in the batteries periodically.

[JohnKen]

Great, from-the-source information! Thank you. The console switch info is especially interesting.

[Mbh818]

Thanks!