How does my Simplicity charging system work?

[nomad1955@centurylink.net]

I have a question or two about the charging system on my recently purchased 2018 RoadTrek Simplicity on a 2017 Ram ProMaster 3500. We, my wife and I, bought it from a private party and there is not any information from the seller. I have watched several videos online about the Simplicity but the information is lacking about the charging system. They all, and the brochure that I downloaded from the internet, tell me that there are two batteries. One battery is the coach battery and the other is the chassis battery (assuming the engine start battery). Our Simplicity has only one battery under the driver's side floor panel. My question is how can a single battery do two jobs without depleting the capacity for either job? I wonder how long we could go without shore power before the van won't start? Also does anyone know where I could find a electrical schematic of the Simplicity and the ProMaster? Thanks

[mumkin]

Roadtrek didn't produce schematics for their customers. Actually the Simplicity is a basic system that is pretty traditional. Yes, you have two batteries (at least... because many of us owners have, like me, added a 3rd.) The starter battery is under the driver's feet on all Promasters. It comes with a manual disconnect on the negative pole if you plan to park it for more than about 10 days. Depending on whether the previous owner or original dealer abused it can go dead rather quickly.

Your coach/house battery is under the van in front of the rear end assembly in a metal box. (the spare tire is closer to the rear bumper) I assume that you also have an underhood generator which is a second large alternator which is just to charge the house battery. (the OEM alternator charges only the starter battery) This alternator provides enough power to run the AC or the microwave at the same time as the engine is running. There is also a 2000w inverter integrated into the system usually on the driver's side on the floor just after the fridge and water heater cabinet.

If you want to find a bunch of Simplicity owners and are a member of Facebook, there is a large group called the Roadtrek Zion and Simplicity Owners. It includes a ton of files for trouble shooting although our Simplicities are not as glitchy as the lithium system vans.

[nomad1955@centurylink.net]

mumkin; Thank you for the information. That was way more informative as any reading or watching videos.

I was thinking that I could have put an aux battery under the van and solve my single battery situation. But now I'm OK. I should have looked more and inspected the van better. As a first time motor home owner I will be learning all the time about camper vans. Again, thanks for replying to my question so soon.

[mumkin]

We're here to help.

You may want to confirm if you have the UHG (2nd alternator). If the seller didn't tell you, you can look under the front bumper on the passenger side. It hangs very low, and we must be very careful not to wipe it out if we get too close to a high curb. They are pricey to replace, but super handy to have if you want to do much camping without a hook-up. It has a small cover, but many of us have added a large metal cover over the whole bottom of the engine. Also, on the inside of the hood is a white label which shows the adjusted belt system. Normally, you should also carry a back up belt as it is an odd size. I've never lost a belt, but many have.

The standard battery is only about 100 amp hours. Most of us Simplicity owners have added a second battery and solar.

[nomad1955@centurylink.net]

Yes I do have the UHG. I am getting a metal shield for it and under the engine and tranny. I also found a spare belt for the 2nd alternator. Am also thinking about a front 1.5" lift kit to level the van better and have a little more clearance at the front.

[mumkin]

Originally Posted by nomad1955@centurylink.net

Yes I do have the UHG. I am getting a metal shield for it and under the engine and tranny. I also found a spare belt for the 2nd alternator. Am also thinking about a front 1.5" lift kit to level the van better and have a little more clearance at the front.

I assume that you are getting the guard from Edge Vanworks?

I installed Sumos front and rear, but they do nothing for the low front end which is standard on Promasters. Take care with lift kits as many of the them will cause Promaster to void part of your warranty.

Any questions or parts needed for the UHG are available from Nations Starter in Missouri who makes these units. You need to check out the belt locations and spacers to avoid interfering with the coolant hoses. Promasters are notorious for coolant leaks even without the UHG.

Do you have the spare tire? Many Simplicity models do not. If you want to add one, some have had one added in the usual space underneath and there is this door carrier which looks good.

https://landedgear.com/products/prom...vU4cztirBb4VvA

[btripper]

great information mumkin. Helped me as well!