How I fixed a chassis battery drain issue on my 26HE

[macdaddy1111]

Wow, thought the Judge was back!

 

[Mark54]

Appendix A: The plot thickens.

I was rummaging around the back of the RV at night, and noticed a faint light coming off of the rear back up camera. I suspect those are infrared LEDs, but why they're on while the Axxera is off is a bit mysterious. It's not something I was looking for while doing this project, but I suspect this too could be a persistent drain on one of the batteries. The kill switch I installed on the Axxera does not disable those LEDs - I was hoping that it would on account of the camera being plugged into the Axxera, but that must just be the video feed, and not it's power supply. I'll investigate further if I find the motivation.

Genius post for sure. But my Tellaro has LFP batteries and chassis is lead-acid, so the BIRD would not be viable. I would need less voltage for the chassis battery, or regulated, so wondering if I should have a Li-BM 225 instead.

I presently have a hardwired trickle charger inside connected to the 120V circuit, and switched manually. Only on when I want it when plugged in and connected to the chassis battery via the Trombetta hot B+ side (bottom post as seen in pic). Drawback would be when boondocking, I have to not sit for more than 10 days, and never have anyways. The Li-BIM would not help in that case. When I drive both get charged anyway- I have two alternators, one for each system.

(Pics after I moved all my electrics off the bottom)

 

[macdaddy1111]

Love the bim 225s

Does great job charging engine and house batteries

Does such great job, my dc/dc charger never comes on!

 

[Jerrygofast]

First thank you SO much @bootenwagen !!

I am a total newbie with my first ever driveable.

I have the same issue of parasitic drain of chassis battery and the same IRD shown in bootenwagen's video.

I have a 200w panel charging my house battery.

I am wondering if instead of the BIRD module- a TRIK-L-START or BIM225 would do the same?

And do both batteries need to be the same type for this type of cross charging solution to work?

 

[Mark54]

First thank you SO much @bootenwagen !!

I am a total newbie with my first ever driveable.

I have the same issue of parasitic drain of chassis battery and the same IRD shown in bootenwagen's video.

I have a 200w panel charging my house battery.

I am wondering if instead of the BIRD module- a TRIK-L-START or BIM225 would do the same?

And do both batteries need to be the same type for this type of cross charging solution to work?

Batteries in the same 'bank' should be same age, color, amps, type, etc. More critical with Lead-acid, in which case, same sales slip, dealer, and saleman... LFPs are more felxible- ReLion says on to add same type and size if less than a year-old.

I sold my two RB100LT's to another 20L owner who had the same year Tellaro as me- so they worked out fine.

You cannot get away with that practise with lead-acids, of any kind, incl. AGM.
The old one will suck the life from the new one when charging, and often overheat and smell of sulfur (classic rotten egg syndrome) Swollen batteries can also result. Don't be smoking near those!!!

 

[Jerrygofast]

same sales slip, dealer, and salesman...

Too funny haha

Okay so just making sure I understand-
For cross charging between the house and chassis battery (via solar to the house battery + some sort of BIRD, BIM225, etc.).
The batteries need to ultimately be as close to exactly the same as possible?

The RV I have is a 2021 freedom elite 26he, I am the third owner and for some reason the previous owners removed the label on both chassis/house batteries... Do you know of a way to test what kind of battery they are?
I have yet to remove them though, maybe the label is on the bottom.

 

[16ACE27]

Too funny haha

Okay so just making sure I understand-
For cross charging between the house and chassis battery (via solar to the house battery + some sort of BIRD, BIM225, etc.).
The batteries need to ultimately be as close to exactly the same as possible?

The RV I have is a 2021 freedom elite 26he, I am the third owner and for some reason the previous owners removed the label on both chassis/house batteries... Do you know of a way to test what kind of battery they are?
I have yet to remove them though, maybe the label is on the bottom.

No, matching batteries is only required for permanent parallel connection, not periodic connection for charging.

 

[Mark54]

Too funny haha

Okay so just making sure I understand-
For cross charging between the house and chassis battery (via solar to the house battery + some sort of BIRD, BIM225, etc.).
The batteries need to ultimately be as close to exactly the same as possible?

The RV I have is a 2021 freedom elite 26he, I am the third owner and for some reason the previous owners removed the label on both chassis/house batteries... Do you know of a way to test what kind of battery they are?
I have yet to remove them though, maybe the label is on the bottom.

Fun job to sleuth what those are w/o labels. No labels will be on bottom- look up specs for the rig to see what they might have been?

Sometimes can ID by case and terminals.

Lead-acids may have caps and a liquid acid, but some can be AGM or SLA (sealed lead-acid) and have no caps at all...

Fully charged Pb-acid batteries will be 12.6VDC and Lithiums 13.6V, so you can test that- but if they are old, might not read that high.

If caps are removeable and can see liquid inside- it's Pb-acid. If below plates, get new ones. You can top off with distilled water, but I would not bother, esp. with you being 3rd owner. I'd want to start fresh myself.

Be sure your charging systems are compatible with whatever you install.
Not all RVs have bi-directional charging either- like the Tellaro/Sequence/Rize/Scope class B's with under-hood generator and lithium coach batteries. In that case, coach and chassis are very separate, and chassis battery will not charge unless engine is running. I had to add an internal charger for my chassis battery to run off inverter.

Important that the 'bank' for the coach all are the same- tho lithiums are more forgiving than lead-acid. Lead-acids have to match in every aspect, lithiums can be a year apart and be "ok".

Good luck!!!

 

[Jerrygofast]

Okay perfect. Thanks for the help everyone!
I ordered a BIRD today for bi-directional charging.
Will report back.

Any recommendations on brand/type for a new chassis battery?

 

[dav5942]

Just checking to see how your mod is working. Looks great!

 

[Life-combing]

Is this a Thor issue?

I am not in anywhere Davy enough to do this. My van is a 2024 on a 2022 chassis. I have just had to have the battery replaced and with in the week it was down to partial charge.
So do it need to be seen and worked on by Mercedes or Thor dealer?
Any help appreciated.

 

[Delta6]

Help to turn off the Main power switch. Does anyone out there
Know how turn off my Main Power Switch off on my 2022 36FA Challenger. Mine just started to say on! By doing so, it is draining my chassis battery! Any suggestions how to troubleshoot and turn the main power off? Thanks for any help out there.

 

[16ACE27]

Help to turn off the Main power switch. Does anyone out there
Know how turn off my Main Power Switch off on my 2022 36FA Challenger. Mine just started to say on! By doing so, it is draining my chassis battery! Any suggestions how to troubleshoot and turn the main power off? Thanks for any help out there.

When you enter the RV, to your immediate left, is your Main Power switch. Push it to OFF. If you are connected to SP the light will NOT go out.

The Main Power switch has nothing to do with your chassis battery.

 

[Beau388]

I am not in anywhere Davy enough to do this. My van is a 2024 on a 2022 chassis. I have just had to have the battery replaced and with in the week it was down to partial charge.
So do it need to be seen and worked on by Mercedes or Thor dealer?
Any help appreciated.

It is my understanding than Mercedes does not allow an interconnection from Thor MC electrical system and the Merc chassis.