Gray Water Sensor Replacement in 320S?

dno

I just got back from a wonderful springtime desert road trip, and my 2019 320s was a total champ throughout all sorts of camping scenarios. Except that the gray water four light indicator never showed anything beyond Empty. It was definitely not empty, as I used about 1.5 tanks of fresh water on my trip, so it should have registered at least 1/3 or even 2/3rds. Today I ran water into the the sink until it started to back out of the shower drain, and the indicator was still showing empty. Is there anything I should try before attempting to replace the sensor, and how exactly does one do that? 

Denny16

Depending on the type of sensor/probe used, you could try adding ice cubes to the tank, and drive around a bit.  Then use Happy Camper and the two should clean the sensor probe to where it will work again.  Otherwise, the shower backing up is a good indication that the tank is full.  
cheers

Sharon_is_SAM

@dno - email tech@nucamprv.com and ask how to proceed.  I think the KIB tank monitors have internal plugs that are replaceable.

dno

OK, SOLVED!
I emailed with support at NuCamp and they felt it was a sensor wire issue. To get to the most accessible part of the wire (hoping for the best) I dropped the part of the belly pan on the driver/front section front and side, a total of about 8 screws. There are a few wires there, and sure enough, the red one had been chewed through by some varmint. I stripped both ends and connected them with a wire nut, buttoned it all up, and sure enough everything's working great again. Woot!

Sharon_is_SAM

Any pictures?

dno

@Sharon_is_SAM
Unfortunately, no, I had to finish in a hurry to go somewhere, but it's all pretty obvious. Remove all the screws in the front driver's side corner area of the belly pan and enough of it comes away that you can clearly see what's going on in there without having to pull off the whole thing. The wires are red, blue, white, and I think yellow, and they go up to where the panel is inside. It's all easy.

Sharon_is_SAM

Is yours the See Level or the KiB?

dno

Sorry, I don't know what those things mean...? It's a 2019 320s.

Sharon_is_SAM

The brand of tank monitor on the panel inside your TaB.  It changed from a See Level tank monitor with external tank sensors to the KIB system with internal tank sensors with the early 2019 models.  Here is a picture of KIB wiring on a black tank.

dno

Ahhh, I see. The panel is a KIB. I'm glad I didn't have to replace the sensor!

Sharon_is_SAM

I don’t think it is too difficult, but nobody wants to dig around in their black tank😊

dno

I've always been a fan of "try the simplest (and least stinky) solution first."