Gray tank reads zero all the time

[sportcoupe]

Searched for posts about gray tank sensors not working, most are about cleaning them because they read partially full or full all the time.

I have a new 2022 Vegas, gray reads empty all the time. It worked for a short time when I purchased rv. I see four wires on my sensors, all are clean and tight connection. How can I test them to see if it's a wiring problem or determine if I have faulty sensor? I added wire colors to the sensors as I see them installed.

[sportcoupe]

I was told I could jumper a test wire from the orange to green wire and touchscreen should read 1/3 full. I did this and the touchscreen display stayed an empty reading.

[javelin]

I don’t know your coach specifics, but if the tank sensors are wired similarly to the attached diagram then it is possible that the sensor string feed wire coming from the monitor panel is accidentally grounded.......which would “simulate” an empty tank, with empty sensor light on all the time. So this could be from an accidental grounding of the sensor string feed wire or perhaps a problem with (or at) the monitor panel itself. A new coach should have the warranty coverage to fix the problem at the Dealer.......after a long wait in line perhaps.

[javelin]

After looking at my first response.....a grounded main sensor string feed wire coming from the monitor panel would probably show "all lights on to full" not empty on all the time as I first stated. The other reason for that always empty sensor being on, could be an "open" sensor string feed wire between monitor panel and sensor string. You could try and see if there is 12vdc at the top of the sensor string with a voltmeter.

[sportcoupe]

I don't have the tank sensor wire diagram. I can see the resistor tank harness and I inspected the other end of the circuit at the BMPro controller.

The tank harness wiring looks like it could have an open in one or more of the wires due to an overly tightened plastic tie wrap. I have ordered the cheap tank harness like the one pictured below. Thor would send it to me if I request. I didn't bother as it's $7 on amazon.