Dead Batteries on 2018 Melbourne 24L

Jeda78 · 07-02-2018, 11:13 AM

Our new Melbourne has been plugged into electricity for about a month. Just tried to start the motor and battery is dead. After checking, both batteries are dead. Any ideas?? Thanks!

Pfflyer · 07-02-2018, 02:50 PM

Plugging into shore power will not charge the starter battery. Mine will last about 2 weeks speaking from experience. Not sure why your house battery would not charge though. Do you have a volt ohm meter to check if the house is getting any voltage at the battery. Could there be a blown fuse on your charger?

Pfflyer · 07-02-2018, 03:04 PM

To solve the starter battery issue I plug a Battery Tender in at the dinette and plug it into the 12v outlet under the so called cup holders. The outlet in the cupholder is ignition controlled but the one under the cupholders is always hot.

Jeda78 · 07-02-2018, 03:23 PM

Well it turns out it was just a misplaced fuse near driver seat. We had taken one out last week to see what kind we would need for replacement and had put it back in wrong slot. Moved it one slot over and all is well. �� Thank you for your response. Will look under cup holder.

Out4Fun · 10-22-2018, 12:17 PM

I've tried to plug a battery tender into the "hot 12v" outlet under the cup holders in the front dash of our 2017 24K sprinter, and get no connection whatsoever ever. I just get blinking amber light forever. Then I hooked up the tender directly to the battery with the alligator clips and allowed the battery to fully charge (with the steady green light showing). Then I retried the cigarette lighter adapter into the 12v plug under the cup holder to see if, now that the battery is fully charged, it shows any sign of life. Still not a connection. So, did Mercedes change things and this is no longer a hot connection, or am I doing something wrong in not getting connection. I'd like to use the adapter in the 12v outlet rather than go through the drill of accessing the main battery.

Pfflyer · 10-22-2018, 03:55 PM

Does that outlet work otherwise? Could be the fuse. As far as I know things haven't changed.

Pfflyer · 10-22-2018, 04:08 PM

I just checked the 2017 Sprinter owners manual (page 206) and it is still hot with the key out of the ignition. If yours is on a 2016 chassis it should be the same. So I would check the fuse.

Out4Fun · 10-23-2018, 07:56 AM

Thank you Pfflyer. I'm going to check today with some other gadget I found that works off a 12v outlet, then check the fuse. I'll let you know.

Out4Fun · 10-23-2018, 04:09 PM

Pfflyer - I've checked the 12v plug under the cup holder - it is hot when the key is out. So, I checked the adapter (the only thing left as the possible problem) and took it apart to find the fuse was blown. I think it may have blown because they have a 3amp fuse in a 5 amp adapter. I'll replace it with a 5 amp fuse (assuming I can find it easily) and try again.

campaholix · 10-23-2018, 04:21 PM

PF: let me see if I got this right...you plugged the electrical cord for the battery tender in the 12v outlet under the dinette and then plugged the cigarette lighter adapter into the socket under the cupholders?
That keeps the chassis battery charged by pulling juice off the coach battery?
How do you keep the coach batter charged?
I've got an extension cord ran to the rig with a battery tender on the coach battery and a second trickle charger on the chassis battery. It works but's it's a pain.

Pfflyer · 10-23-2018, 06:20 PM

Quote:

Originally Posted by Dnbgould

PF: let me see if I got this right...you plugged the electrical cord for the battery tender in the 12v outlet under the dinette and then plugged the cigarette lighter adapter into the socket under the cupholders?
That keeps the chassis battery charged by pulling juice off the coach battery?
How do you keep the coach batter charged?
I've got an extension cord ran to the rig with a battery tender on the coach battery and a second trickle charger on the chassis battery. It works but's it's a pain.

Its the 120v outlet under the dinette. I plug into a 120v 20amp home outlet through the shore power inlet when at home so that is what charges the coach battery through the converter and powers the 120v outlet under the dinette which powers the battery tender.
You could get an adapter and plug into the shore power inlet instead of running the extension cord into the coach.

Out4Fun · 10-24-2018, 10:21 AM

My set-up is not through the coach battery but rather directly from shore power to the chassis battery using a battery tender trickle charger (12v 5 amp). I'm trying to avoid having to access the battery under the drivers side floor panel. I was hoping to connect the tender directly and effortlessly to the chassis battery power through a hot 12v socket under the cup holders in the middle of the dash. I think with a new fuse (5 amp) in the adapter, this will still work.

Pfflyer · 10-24-2018, 11:00 AM

Quote:

Originally Posted by Out4Fun

My set-up is not through the coach battery but rather directly from shore power to the chassis battery using a battery tender trickle charger (12v 5 amp). I'm trying to avoid having to access the battery under the drivers side floor panel. I was hoping to connect the tender directly and effortlessly to the chassis battery power through a hot 12v socket under the cup holders in the middle of the dash. I think with a new fuse (5 amp) in the adapter, this will still work.

It is possible to charge the chassis battery through the jumpstart posts under the hood instead of through the drivers floor panel. I have a 2 bank battery charger and that is what I used after I first got the RV. I connected one set of leads to the jumpstart positive post under the hood and a ground post and the other set of leads to the coach battery. I didn't like the cords on the ground and the extra effort to connect both batteries before and after the trip. My current set up is what I had planned all along but there are other ways to do it as well.

If you aren't aware you can also disconnect the chassis battery fairly easy via the disconnect above the throttle pedal. The procedure is spelled out in the Sprinter's owner manual along with the location of the jumpstart posts.

campaholix · 10-24-2018, 03:16 PM

Quote:

Originally Posted by Out4Fun

My set-up is not through the coach battery but rather directly from shore power to the chassis battery using a battery tender trickle charger (12v 5 amp). I'm trying to avoid having to access the battery under the drivers side floor panel. I was hoping to connect the tender directly and effortlessly to the chassis battery power through a hot 12v socket under the cup holders in the middle of the dash. I think with a new fuse (5 amp) in the adapter, this will still work.

I'm doing what PF described...I have a trickle charger under the hood for the chassis battery and a battery tender inside the house battery compartment keeping that battery charged up. I just didn't realize you could use the battery tender to charge the chassis battery thru the cigarette lighter...would make it just that much easier than getting under the hood every time I need to check, disconnect, or reconnect.

TGLOWKA · 11-10-2018, 06:16 PM

On my 2019 24L, there are POS and NEG poles under the hood where I connect my battery tender.

Out4Fun · 11-11-2018, 01:46 PM

On our 2018 24K and Sprinter, there was some exotic way to connect under the hood, but I could never figure it out. I'm pleased with the eventual solution we have of a battery tender plugged into the 12v socket under the dash cup holders. I use a 5 amp fuse in the adapter, and it is working great.

bababooey · 11-11-2018, 02:55 PM

Nothing to mess with anymore..

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