Battery Melbourne Mercedes

[Mellonracing]

We recently purchased a 2020 Melbourne on the Mercedes chassis.
The engine / chassis battery keeps going dead in less than a week. And yes, everything inside is turned off.
The Mercedes owner's manual mentions a 3 week period of no use may result in a dead battery. So there is an obvious known draw down right from Mercedes.
I was thinking of installing a Trick-L-Start (name brand) to keep the engine / chassis battery charged when the coach is plugged into shore power. It works through a connection to the house battery.
Has anybody installed one of these or a similar on-board trickle charger / battery maintainer?
This is our third camper so I am somewhat familiar with RV electrical systems. My previous two were on Chevy chassis which never gave me a problem.
Thanks in advance for any help or advice.

[RetiredOne]

Two things... that battery drain issue has been mentioned a few times here. If I remember, believe a relay under the driver's seat is the problem. Try doing a search above for Melbourne battery drain, and the threads should pop up, and tell you how to bypass it.

Regarding the Trik-L-Start, a bunch of people have installed them and like them. It will keep the chassis battery charged when plugged into shore power.

[Midnightmoon]

There should be a factory battery disconnect near the throttle pedal on the Sprinter.

[Mellonracing]

Thanks for the reply.
Yes I did see the disconnect. I have not tried it yet because I'm not sure if it will reset the truck's clock and/or the entertainment center settings. I certainly don't want to reset them each time I get in to go someplace. It isn't addressed in the manuals.

[Pfflyer]

Welcome to this forum as well. The attached PDF is a solution to an issue to "some" 2017 Melbourne's. I put some in quotations because I don't think they changed the way they wire it since then due to the way this relay is supposed to work. Apparently this has solved the issue with another user here. Mine will last about 2 weeks and I think the user that posted this solution from Jayco would last days like you. As stated in the Sprinter forum, I use a Battery tender plugged into an always hot 12v outlet connected to the chassis battery. I am not sure if the latest version Sprinters have this but it should say in your owners manual or you could test the chassis 12v outlets while the ignition is off.

Battery Draw Jayco rewire diagram.pdf

[RetiredOne]

Originally Posted by Pfflyer

As stated in the Sprinter forum, I use a Battery tender plugged into an always hot 12v outlet connected to the chassis battery. I am not sure if the latest version Sprinters have this but it should say in your owners manual or you could test the chassis 12v outlets while the ignition is off.

This is actually what I do when my rig is sitting for a while. I was going to install a Trik-L-Start to keep the chassis battery charged, but I had an extra battery tender sitting around, so I just plug the battery tender into the outlet under the dinette, and I put a male plug on the output, and plug it into one of the dashboard receptacles, that are hot all the time from the chassis battery.

During the Winter, instead of having the complete 120 volt system energized when plugged into shore power, I ran a second battery tender to the house batteries. I didn't want to pull all the batteries out, in case I needed to move or use the rig during the Winter.

Then, I put a digital timer on both of the battery tenders, so they only cycle on twice a week. This is more than enough to keep the batteries topped off, without needing them to be plugged in 24/7.

[Still smiling]

Hi Everybody,

Our 2019 Melbourne Prestige lost all three batteries
twice before we went to Mercedes. The problem
happened out of nowhere after parked for a few days. Once the issue started we lost two house batteries first and then all three within three days. Long and short.... after Mercedes could not find the source of the par acidic drain I called Jayco
And they said it was the emergency brake and they sent us the wire workaround which we gave to the
Tech. Problem solved. Others have said the had same issue. Hope my input helps others. Stay safe out there🚚☮️

[Pfflyer]

Originally Posted by Still smiling

Hi Everybody,

Our 2019 Melbourne Prestige lost all three batteries
twice before we went to Mercedes. The problem
happened out of nowhere after parked for a few days. Once the issue started we lost two house batteries first and then all three within three days. Long and short.... after Mercedes could not find the source of the par acidic drain I called Jayco
And they said it was the emergency brake and they sent us the wire workaround which we gave to the
Tech. Problem solved. Others have said the had same issue. Hope my input helps others. Stay safe out there🚚☮️

Thanks for the update.

[jkaras7]

Originally Posted by Pfflyer

Welcome to this forum as well. The attached PDF is a solution to an issue to "some" 2017 Melbourne's. I put some in quotations because I don't think they changed the way they wire it since then due to the way this relay is supposed to work. Apparently this has solved the issue with another user here. Mine will last about 2 weeks and I think the user that posted this solution from Jayco would last days like you. As stated in the Sprinter forum, I use a Battery tender plugged into an always hot 12v outlet connected to the chassis battery. I am not sure if the latest version Sprinters have this but it should say in your owners manual or you could test the chassis 12v outlets while the ignition is off.

Attachment 63521

This is exactly what we had to do to keep the engine battery from going dead in a week or less. Jayco sent us this fix as well.

[Mellonracing]

Installed Trik-L-Start several months ago and all was well for several trips. Never did the under seat relay re-wire that several suggested here and other forums. Took a trip from Connecticut to Maine in July. Full hook ups at site. Ready to leave at the end and chassis/engine battery was dead. Jump started and made it back to CT without a problem. Plugged into shore power immediately when home. Went to leave on a long weekend trip last Friday and the chassis/engine battery was dead again. In both cases, the emergency start button was used but would not start the engine. Meter on the panel showed full charge for the house battery and the house battery started the generator without a problem. So jumped it again from my car and drove 45 miles (mostly highway) to campground. When leaving Monday, battery was dead again and needed a jump. The house battery wouldn’t do it with the emergency button. So confusion rules. The Trik-L-Start should have kept the chassis/engine battery up. And the long rides should have charged the engine battery by the alternator. In addition, the fully charged house battery should have started it using the emergency button. Not sure what to try next.

[Pfflyer]

Originally Posted by Mellonracing

Installed Trik-L-Start several months ago and all was well for several trips. Never did the under seat relay re-wire that several suggested here and other forums. Took a trip from Connecticut to Maine in July. Full hook ups at site. Ready to leave at the end and chassis/engine battery was dead. Jump started and made it back to CT without a problem. Plugged into shore power immediately when home. Went to leave on a long weekend trip last Friday and the chassis/engine battery was dead again. In both cases, the emergency start button was used but would not start the engine. Meter on the panel showed full charge for the house battery and the house battery started the generator without a problem. So jumped it again from my car and drove 45 miles (mostly highway) to campground. When leaving Monday, battery was dead again and needed a jump. The house battery wouldn’t do it with the emergency button. So confusion rules. The Trik-L-Start should have kept the chassis/engine battery up. And the long rides should have charged the engine battery by the alternator. In addition, the fully charged house battery should have started it using the emergency button. Not sure what to try next.

Did you ever put a meter on the chassis battery to make sure it is being charged when plugged in? Your starter battery may have been discharged too many times now and is dead.