Master Volt Switch cable in 2020 View

[Sea Man]

In the process of replacing the original 2 x 100amp wet cell batterys with a 300 amp LiPo4 battery.

under passenger seat is the MasterVolt 40 which regulated voltage and current (40 amps unfortunately ) between chassis / altenator and house batteries.

There is a terminal on the master volt for a 'switch' that allows an override to allow the house battery send power to the chassis battery

on my 2020 view, there is a yellow wire connected to this terminal , wire is labeled LR and its listed in the Winnebago wire ID chart as
'LR / 14 YEL BATTERY MODE SWITCH (AUX START SWITCH) '

Does anyone know where this wire goes to ?

I assume it goes to a switch somehwhere or at least goes to a place where I can add a swtich

I cant seem to find such a switch in the vehicle

any help appreciated

[Morich]

That's a long time wire setup that has been around for decades but has gone from an older type to newer solid state!
Lr is the wire that sends power from a switch near the driver. It is used when we want to "jump start" a weak chassis battery. LR for positive battery and FM to bring ground to the setup.
I did not study your RV enough to spot the switch but should be a momentary toggle switch labeled something like "AUX", Aux start, Boost or something that might clue you that it connects the two battteries together! Got any switches near the dash/driver that you never use or maybe even questioned?
The second use for this wire LR is that it is also connected to what many chassis folks call "ignition hot". I've never known exactly where to find that point but it is as the name implies, a point that is only hot when the ignition is on! That means 12V is hot on LR to connect the two groups when we drive. That lets us put some charge back into any battery we may have run down while dry camping.

Check sheet 7 of this drawing to see where and how that set of wires is connected down under the passenger seat?

Point for you to look into but not one I have worked/studied enough to say, is the way this may complicate a change to lithium! I read more than I KNOW on that! But the talk is that the lithium can draw more power and when connected to the engine alternator runs a risk of overheating it!
Heads up on the question but I'm not the best to talk about it. Not been my game and others here are far better to talk it over!

[bigb]

On my 2010 Sprinter chassis the boost switch is located in a panel right above the factory cup holder. So if you think they pre-wired for it maybe look back in there? If you need to remove the trim bezel it's fairly simple, it just unclips from the dash, then there are screws holding in the radio, HVAC control and the panel with the hazard switch in it.

You may be able to just remove the cup holder and look up in there.