When you say, everything is full on, do you mean all tanks, even the fresh tank shows full when when the tank is empty and you press the "fresh" button?
Please confirm before I type a bunch on the wrong problem.
I have had to trouble shoot mine, different model (newer) but same problem and same KIB brand. In my case the wire up from the tank was skinned shorting out to the frame ground and was getting a wrong signal. It would never stop reading full when I pressed it until I found the problem.
Do you have a volt/ohm meter?
We can back into taking the tank wires off 1 at a time on the back of the unit and figure out if it is a wiring issue or the main board is bad. Not hard to do with basic electrical skills
Hope this helps
PS. Thanks for the pic. it is worth a million words in these cases so we know exactly what you have
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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