No lights on tank level test when buttons pushed 2019 GD Reflection 303RLS

[Almost There]

Afternoon everyone
I’m hoping someone here has some experience with the holding tank level sensing system.

On the convenience center as per attached photo you can check battery state of charge, fresh water tank level, black and 2 grey tank levels.

Battery test works, fresh water works but the black and 2 greys don’t. The lights don’t light at all.

I’ve pulled the panel out and the levels all come off a printed cct board.

Hoping that someone has solved this problem and can possibly point me in the right direction.
Testing procedures, routing of the sensor wires, anything!
Is it a common ground and the sensors connected to positive and run through resistors so different return voltages correspond to levels?

I’ve been looking for some form of drawing online but nothing there.

I know the levels are notorious for being inaccurate but would like to get this thing working while I’m away but seriously thinking about installing the system that is on the outside of the tanks once I get home where I have all my tools etc.

 

[jkwilson]

Generally there are 4 connections into each tank. One ground and three level electrodes. The level electrodes are at the 1/4, 1/2 and 3/4 levels, with the ground at the 1/4 level. The ground is common to all the tanks and should have a frame connection rather than a feed from the panel, though the panel probably gets its ground from the same spot.

The panel just shows the highest sensor that has continuity to the ground electrode. All of the tank electrodes run back to the panel. IIRC, there is a bundle of 4 wires from each tank, with one not used.

My guess is you have a break in the ground between your fresh water tank and the other tanks. This seems a likely place for a problem, since the fresh tank is behind and slightly separate from the holding tanks.

You can get to parts of the holding tanks by taking the basement wall down (easy), but I don’t remember whether you can get to any of the sensor wiring from there. Otherwise, you can take some screws out of the coroplast on the curb side between the pass through door and the entry door and take a look inside to see exactly where you need to take more screws out.

 

[Almost There]

Thank you John, appreciate the info.

 

[Nutz4OSU]

Afternoon everyone
I’m hoping someone here has some experience with the holding tank level sensing system.

On the convenience center as per attached photo you can check battery state of charge, fresh water tank level, black and 2 grey tank levels.

Battery test works, fresh water works but the black and 2 greys don’t. The lights don’t light at all.

I’ve pulled the panel out and the levels all come off a printed cct board.

Hoping that someone has solved this problem and can possibly point me in the right direction.
Testing procedures, routing of the sensor wires, anything!
Is it a common ground and the sensors connected to positive and run through resistors so different return voltages correspond to levels?

I’ve been looking for some form of drawing online but nothing there.

I know the levels are notorious for being inaccurate but would like to get this thing working while I’m away but seriously thinking about installing the system that is on the outside of the tanks once I get home where I have all my tools etc.

 

[Nutz4OSU]

I had the same issue. Was under warranty so I took my Reflection to the dealer. As some others have noted, it was merely a loose (actually detached) ground wire. Once reconnected, all sensors worked flawlessly, and have stayed “connected” ever since.

 

[Almost There]

Thanks for taking the time to reply.
I’ve pulled the panel inside and looked at the wires coming off the printed circuit board, they join to wire that goes down to basement. All joints are intact and appear fine. I’ve probed the solder points on the cct board, I do have 12V pos and neg into board. I’ve removed the wall in pass through hoping that I could see something, anything but no luck.
Weather in Florida hasn’t been the best to consider dropping the coroplast and to be honest I don’t have any idea where on the frame the tanks are located so I haven’t tried anything there yet.

 

[Almost There]

ad the same issue. Was under warranty so I took my Reflection to the dealer. As some others have noted, it was merely a loose (actually detached) ground wire. Once reconnected, all sensors worked flawlessly, and have stayed “connected” ever since.

By any chance when yours was fixed did the dealer give you any indication where the grounding was done?
I just don’t look forward to dropping the coroplast the entire length of the trailer.

 

[Nutz4OSU]

By any chance when yours was fixed did the dealer give you any indication where the grounding was done?
I just don’t look forward to dropping the coroplast the entire length of the trailer.

Unfortunately they did not. However - I am assuming that it was at the panel, as (I do not believe) they dropped the coroplast.

 

[jkwilson]

Thanks for taking the time to reply.
I’ve pulled the panel inside and looked at the wires coming off the printed circuit board, they join to wire that goes down to basement. All joints are intact and appear fine. I’ve probed the solder points on the cct board, I do have 12V pos and neg into board. I’ve removed the wall in pass through hoping that I could see something, anything but no luck.
Weather in Florida hasn’t been the best to consider dropping the coroplast and to be honest I don’t have any idea where on the frame the tanks are located so I haven’t tried anything there yet.

As I mentioned above, if you take down the basement wall you can see the tanks so you’ll know exactly where they are.

 

[Almost There]

As I mentioned above, if you take down the basement wall you can see the tanks so you’ll know exactly where they are.

Thanks John, I did remove the basement wall but didn’t see the tanks. I know where the black tank is because I see toilet pipe but couldn’t see anything else.
When weather is a bit better I’ll remove wall again and crawl into the pass through to see if I can get a better angle.

 

[traveldawg]

I'll guess the common ground the 3 tanks use is bad. And I'll guess the connection is in the underbelly tank area. I did some internet searching and it seems a lot of various tank sensor schematics show those grounds to be common.

I think your tank (and basement) layout is similar to mine. If I remove the back wall I can see the rear of the black and main gray tanks (and maybe the valves); but you can't get to anything to do any work. On mine there might be a very slight chance I could get a long stick and wiggle some wires on the back of the tanks from the storage area - but only maybe.

Here is a photo of my tanks with the coro-last dropped. The wiring is just a mess but you can see the many tank probe wires.

I'll post an old wiring diagram that is part of a full set from years ago that a member name Klenger posted. Klenger's 297RSTS Diagrams.

 

[Almost There]

Morning Larry
Looking at your photo gives me a better idea where to look. I hope that Grand Design didn’t change the location of the tanks too much.
You’re right, the wiring from what I’ve seen is an absolute mess, quite honestly, overall there doesn’t seem to have been much pride in the building of the trailer.
Not sure yet if I want to do this while in Florida or wait till I get home where I have majority of my stuff. Plus the weather here has been real good recently.
The gent that did the drawing, all I can say is WOW, very impressive.
Larry, thank you for the information and drawing, I really think it will be helpful.
I’ll post updates and get photos when I attack this job.

 

[Slowbell]

Afternoon everyone
I’m hoping someone here has some experience with the holding tank level sensing system.

On the convenience center as per attached photo you can check battery state of charge, fresh water tank level, black and 2 grey tank levels.

Battery test works, fresh water works but the black and 2 greys don’t. The lights don’t light at all.

I’ve pulled the panel out and the levels all come off a printed cct board.

Hoping that someone has solved this problem and can possibly point me in the right direction.
Testing procedures, routing of the sensor wires, anything!
Is it a common ground and the sensors connected to positive and run through resistors so different return voltages correspond to levels?

I’ve been looking for some form of drawing online but nothing there.

I know the levels are notorious for being inaccurate but would like to get this thing working while I’m away but seriously thinking about installing the system that is on the outside of the tanks once I get home where I have all my tools etc.

Just change out the board on control panel. It’s probably bad. Mine did same thing for black tank all others worked. Once I changed the board everything worked fine. It’s easy to change out.

 

[Almost There]

Just change out the board on control panel. It’s probably bad. Mine did same thing for black tank all others worked. Once I changed the board everything worked fine. It’s easy to change out.

Thanks for taking the time to reply.
Unfortunately the only indicators that work are the battery and fresh water tanks, both grey and black do nothing.
Would be easy if it was just the board

 

[Slowbell]

On mine all lights worked on all except for the black tank 2. I changed out the board from the one I purchased through Grand Design and fixed the problem. It’s a plug and play easy fix. Not sure if you tried it first but it’s a cheap fix if that’s all your problem is. Chasing wires is very frustrating and very time consuming. Most problems I have had are simple fixes. Most people overestimate the potential problems that they run into.

 

[traveldawg]

Morning Larry
Looking at your photo gives me a better idea where to look. I hope that Grand Design didn’t change the location of the tanks too much.
You’re right, the wiring from what I’ve seen is an absolute mess, quite honestly, overall there doesn’t seem to have been much pride in the building of the trailer.
Not sure yet if I want to do this while in Florida or wait till I get home where I have majority of my stuff. Plus the weather here has been real good recently.
The gent that did the drawing, all I can say is WOW, very impressive.
Larry, thank you for the information and drawing, I really think it will be helpful.
I’ll post updates and get photos when I attack this job.

@Almost There
Bob,
I had a lot of free time and got curious how tank sensors with multiple probes could use jut one wire to relay the tanks levels. I came across this video. It is pretty informative. Now I'm wondering if one could just measure the resistance of the tank probes at the panel to determine if they work right.