Chassis battery died on 2018 Serenity

slinkblot

New member
We just got our 2018 Serenity two weeks ago. My husband and I are completely new to this whole adventure. We have been learning everything about it until we take it out in January on our first planned trip.

As we tested everything and studied all the details, while plugged into land power, we played music on the radio of our entertainment system. Later that evening, we decided to take it out to fill it up (diesel). The battery was DEAD! We have 96 miles on it and the battery was DEAD! How is the entertainment system (Jensen) running off of the chassis battery? That system has the DVD Player for the TV, music, etc ... Shouldn't that be running on the house batteries? If that isn't what killed the battery, we don't know what did!

We scoured the manuals and can't even find which source of power the entertainment system is running on!

Any ideas?
Slinkblot
 

Buckyburrows

New member
Ignition on ? Test the chassis battery voltage with a meter. Check the battery separator with meter. When plugged in to shore power, both terminal read the same. When not on shore power, one side will show voltage of house and the other side will be chassis battery voltage. Make sure of a good ground on the meter.
There are a myriad of issues that could drain the battery but you have to start somewhere. A good digital voltmeter is indispensable.


Sent from my iPhone using Tapatalk
 

Mike DZ

2016 View 24V (2015 3500)
Not a Serenity guy, but entertainment center is not likely to be wired to chassis battery. And even if it was, a few hours of radio playing should not take a "new" battery down to dead. With a 2018 sounds like time to call a MB dealer and exercise the warranty. There are a few threads on early dead chassis batteries on the forum.

Edit: A battery boost switch that uses the coach batteries to assist in starting is pretty standard in RVs - perhaps your Serenity has one?
 
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Not a Serenity guy, but entertainment center is not likely to be wired to chassis battery. And even if it was, a few hours of radio playing should not take a "new" battery down to dead. With a 2018 sounds like time to call a MB dealer and exercise the warranty. There are a few threads on early dead chassis batteries on the forum.

Edit: A battery boost switch that uses the coach batteries to assist in starting is pretty standard in RVs - perhaps your Serenity has one?
This appears to be a defective battery or one of the chassis operated systems malfunctioning. Keep in mind that the stabilizers (if equipped) and the side door step... both are set up to retract the moment the ignition key is put in the run position. That is for safety in case you forget to retract them. There should be a micro switch that shuts off the power when either system is retracted. A malfunction there could be drawing down the chassis battery.

I'm pretty sure that the Serenity does not have a 'boost' switch that allows the engine to start from the chassis battery. Mercedes prohibits LTV from installing this on newer units. The only other item that I can think of that draws chassis power might be the isolator relay. That unit energizes a coil to close a contactor that connects the engine charging system to the house batteries. That system is not suppose to activate unless the ignition switch is in run and the engine has been running for a few minutes. It is unlikely that is bad.

Call LTV or Mercedes roadside assistance and have them come out and test your battery. It might just be bad. There is a slight chance your charging alternator on the engine could be bad.

Operating the coach entertainment system should not have affected the chassis battery system. Good luck getting this addressed with no hassle.
 

geds

2018 Serenity
Our 2015 Sprinter chassis Winnebago Era had a switch on the center of the dash below the radio to redirect the power supply for the radio from coach to house batteries. The Mercedes Owner's Manual described the feature (if I remember correctly). And the switch was adjacent to the battery boost switch for use in "jump starting" the coach from the house batteries. I ran the coach down on one of our first trips and used the boost switch to start the engine. Mercedes also warned to remove the keys from the ignition when the engine was off to prevent power drain.

I assume our new Serenity (pick it up in April) will have these same features as they were Mercedes features.
 

ptheland

2013 144" low top Passgr
... we played music on the radio of our entertainment system. Later that evening, we decided to take it out to fill it up (diesel). The battery was DEAD!
Just to be sure, you're talking about a radio somewhere in the rear of the coach, not the radio in the dash?

A radio in the top center of the dash console is probably running off the chassis battery and not the house battery. Your coach builder would have to change the factory wiring to switch that radio over to the house battery. Some might take the time to do that, some won't.
 
Our 2015 Sprinter chassis Winnebago Era had a switch on the center of the dash below the radio to redirect the power supply for the radio from coach to house batteries. The Mercedes Owner's Manual described the feature (if I remember correctly). And the switch was adjacent to the battery boost switch for use in "jump starting" the coach from the house batteries. I ran the coach down on one of our first trips and used the boost switch to start the engine. Mercedes also warned to remove the keys from the ignition when the engine was off to prevent power drain.

I assume our new Serenity (pick it up in April) will have these same features as they were Mercedes features.
If it has a boost switch... please let me know (post back here). I was told 'no more' because of Mercedes' directives.
 

Old Crows

Calypso 2014 View Profile
We just got our 2018 Serenity two weeks ago. My husband and I are completely new to this whole adventure. We have been learning everything about it until we take it out in January on our first planned trip.

As we tested everything and studied all the details, while plugged into land power, we played music on the radio of our entertainment system. Later that evening, we decided to take it out to fill it up (diesel). The battery was DEAD! We have 96 miles on it and the battery was DEAD! How is the entertainment system (Jensen) running off of the chassis battery? That system has the DVD Player for the TV, music, etc ... Shouldn't that be running on the house batteries? If that isn't what killed the battery, we don't know what did!

We scoured the manuals and can't even find which source of power the entertainment system is running on!

Any ideas?
Slinkblot
G'day! Oh Dear!!!! What a way to start your ownership..... OK, lets see if we can help. Not a Serenity owner.... but, about 99% of the modern RVs use similar strategies for battery charging and use.

1. There are two battery systems: chassis (starts van & runs dash radios, GPS, etc.); coach system (runs all the other 'stuff' in the coach).

2. The coach has a 'MASTER ELECTRICAL' switch. ON when using the coach amenities, fridge, water heater, water pump.... everything in the coach. OFF when not using the stuff in the coach!!! Generally, you can charge the coach battery bank with MASTER OFF.

3. The Sprinter (chassis) system runs everything Sprinter... nothing in the coach. Key should be OFF & OUT when parked. IDK about Serenity, but Views and Navions have two switches on the dash. One allows you to run the radio/entertainment/gps from the COACH batteries OR the chassis battery. The chassis selection is key controlled by the ignition key. So switch to Chassis ... unless you want to use the chassis battery for entertaining or programming GPS. If you leave the ignition ON (or key in ignition) AND the the radio switch ON, it will run the chassis battery down. Confused yet???

OK... Ignition OFF, dash switch to Chassis, and COACH MASTER OFF... when leaving the coach/van.

Charging strategies:

Shore power or generator will only the charge the coach battery! It provides 110V AC to those things needing it (HVAC, WH, fridge) AND 12V DC for those other things in the coach (LED lights, water pump, furnace motor, etc..)

Shore power or generator WILL NOT CHARGE the chassis battery!!! EVER....!!!

The Sprinter's alternator will charge BOTH battery sets when the engine is running. It also provides 12V DC for the Sprinter's amenities AND the coach's 12V DC 'stuff.'

Possible reason for dead battery: it' is bad; or, you left the ignition on, key in, or entertainment 'switch' to chassis rather than coach. Also, batteries are not "Harry Potter" devices. You don't wave a wand and instantly charge them. It takes a few hours, usually, to bring them up to full charge. It aint' 'magic'!! So you could have had a battery that was not fully charged to start with. So... first we need to check the charge in the batteries.

Your Serenity probably has a panel that shows you the levels of fluids in the various tanks AND the charge on the batteries. Our View will show battery voltage (state of charge) for both battery sets. Without starting up anything and shore off*, first thing to do is turn on the MASTER COACH (no other draws except maybe an LED light to see what you are doing)..... Go directly to your panel and check the SoC. You may be reading volts directly or it may be several LED lights (F, 3/4, 1/2, 1/4) or something like that. That's your reference....

* if on shore power... disconnect and wait about 5 minutes & turn on an over head LED light to take off the surface charge on the battery. That will give you a bit of a truer reading.

STARTING STRATEGIES: Obviously, a dead/low chassis battery won't start the van. There maybe a switch on the dash that allows you to 'slave' the coach battery to the 'low/dead' chassis battery. On a View/Navion you hold the 'slave' switch ON whilst turning the key to start. Once started, the Sprinter will run and charge batteries on it's own.

If the coach battery is also low.... start the genny, if you can. You may be able to MacGuyver as start by 'reverse slaving' the batteries. Get someone to hold the salve switch ON while someone else starts the genny. Once running, the genny will provide 110V and charge the chassis.

Last, I'd not fret over running the battery down..... once or twice is probably no big deal in the long term. Just charge it up and double check what you are doing to avoid running it down.

SoC Chart: Print out and tape near your control panel....

https://drive.google.com/open?id=1dSBhn-zwWUwmgC0JPd5NzNPq3JA8l8J6
 
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slinkblot

New member
No... It's the entertainment system in the coach. We're at a loss and will be pulling out the warranty card on the dealership that sold us the Serenity. We didn't have the keys in the ignition at all during the whole time we were listening to the music.

My husband checked the voltage with his meter and it appears to be at 12V now after having charged it last night and running it for awhile. We will definitely be calling on our dealership tomorrow to handle a few problems... but the battery is our biggest problem! Thank you all for your help.
 
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Mike DZ

2016 View 24V (2015 3500)
Engine no start (and chassis battery) is a MB issue, not an RV dealer issue. RV dealer will likely refuse to work on this issue - not because they don't want to help, but they aren't allowed to.
 

slinkblot

New member
We haven't had an issue since that one time. We're still bringing the Serenity into the RV Dealership where we bought it to have the chassis battery tested. They are going to order a new battery if they find any fault with it.
 

pfflyer

Well-known member
I don’t have your make or model but, like previously said they are all built similar. If you haven’t started the engine in two weeks that’s about how long my chassis battery will last without being charged some how. The Co2 monitor and coach power steps are at least 2 items that are powered off the chassis battery and will drain the chassis battery over time. I am sure there are more but when in storage and plugged into shore power, I plug a battery tender in the 12v socket under the ashtray to keep the chassis battery happy. Congratulations on your purchase by the way.
 
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slinkblot

New member
Started out on a trip and the battery was dead... again. After a jump, we got it into a Mercedes service center and they replaced the battery. No more problems or worries on the trip with regard to the battery! It failed all tests, by the way!
 

4wheeldog

2018 144" Tall Revel
Started out on a trip and the battery was dead... again. After a jump, we got it into a Mercedes service center and they replaced the battery. No more problems or worries on the trip with regard to the battery! It failed all tests, by the way!
A small percentage of all new stuff is defective. Hopefully, it was just a bad battery from the get go, and your problems are behind you.
It is also entirely possible that the battery was run down accidentally during coach construction, and left dead.........And it was jumped or charged before shipping it out. This seriously shortens a battery's life at best, and can kill it immediately at worst.
So it may not have been the manufacturer's or MB's fault, but the fault of the assemblers.
 

EBH

Member
It is all spelled out in MB manual, re: battery maintenance .
It is worth well to read it and get up to date on your vehicle and handling procedures .
I'm on my second Sprinter and always learn something new.
Enjoy!!
 

Bobnoxious

Made in the USA Qualité Supérieure
There's a date code stamped on the positive post. At least on Varta batteries

For optimum vehicle electrical system and battery performance, the owner's manual and Builders Equipment Guide suggests battery maintainer for storage longer than three weeks.

Last I checked, my battery was 5.5 years old and I always use a maintainer. Storing vehicle indoors, especially during winters and northern latitudes, may contribute to longer battery life.
 

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