SeeLevel II potable water tank gauge wonky


Staff member
My previous thread on this problem:

The SeeLevel II system in our Airstream has worked pretty well with exception of the fresh water tank gauge. Our model is the 709-P3 which displays the levels of all three tanks (fresh, gray, and black), battery voltage, and a power switch for the fresh water pump.

Within the first month of when we bought the Airstream new, I would see a "0" on the display for the fresh water tank when I knew the level wasn't zero. This only happened occasionally and never bothered us. Over the first couple years of ownership the problem got worse until last summer the fresh tank would read "0" most of the time, but occasionally would read the correct value or a seemingly random value.

We took the trailer back to Airstream this fall for it's 2 year end of warranty checkup and had a few other things fixed. They looked at the SeeLevel and recrimped the fresh tank wiring between the display panel and the tank sensor. They filled and drained the fresh tank three times and the gauge worked perfectly every time. I have no doubt that the gauge was working when they tested it. The Airstream service center has a great reputation for doing high quality work. When I picked the trailer up the tank was empty and the gauge read empty, so there was no way the gauge could be tested.

We left on a trip a couple days later and low and behold the gauge displayed "0" when the tank was full. :mad:

I called Garnet, who makes the SeeLevel, and talked to Dean. We discussed the problem for several minutes. I described that the gauge will read 0 or anything from 0 to 100% when the tank is full and anything between the correct value and 0 when the tank isn't full. There was also one behavior of the display that I noticed a few times. The red numbers on the display will pulse brighter for just a moment then return to the normal brightness. Dean had not heard of this, but went off to talk to a couple colleagues. When he came back to the phone he said that one of the other guys had never seen the pulsing, but had heard of it happening a couple times before and from an engineering standpoint it is possible under certain malfunction conditions and would explain what I'm seeing and the inaccurate display values.

Garnet is sending me a new display panel under warranty.

The customer service I received from Garnet has been fantastic plus I never had to wait on hold. I'm a big fan of Dean and Garnet Industries.

I sure hope the new display panel fixes the problem, because I sure don't want to have to replace the sender on the tank.

We'll see.
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New display and pigtail came today free of charge.

Sounds like pretty good customer service!
Yes, every time I've called, Dean has answered the phone and been very helpful. They warrantied this, even though it was out of warranty, because it was a defect in the receiver. I'm a bit fan of Garnet!
I was able to replace the display last weekend. The display no longer pulses and no longer displays "open", so it does appear that the display was faulty. You know there has to be a "however", so here it goes. The potable water tank is empty, but the display now says it's 50% full.

Original display with potable water tank displaying "open"


Identical units


50% display with new display, but the tank is empty.


I'm hoping the sender isn't bad, because it's in here:


I was able to get a picture of the sender, but it took a herculean effort to get the phone and flashlight into position to take the picture.

I just got off the phone with Garnet. Have a mentioned what wonderful customer service they have?!

The tech that I spoke to said that the most common reason the sender would calculate an erroneous tank reading is anything metal near the sender. Do you see what's in the lower left corner of the picture I posted above? Two wires hanging in near the sender. The wires are only an inch or two from the sender, which is close enough to interfere. He said this could very likely be why the sender thinks the tank is 50% full. I'll tie the wires back and then see what the gauge says. He did say the sender is sensitive enough that just running your hand close to the sender will change the calculated level of the tank.
I tied all the wires up as far away from the sender as I could. Guess what? They gauge now displays the proper tank level - 0%. Always keep anything metal as far away from the sender as you can.

It was just my luck to have two problems with the system I was troubleshooting. It sure makes it more challenging!

The SeeLevel is now working perfectly after replacing the faulty display and tying all the wires away from the sender.

We sold the Airstream, so the next owner will enjoy a properly working tank monitor!