Leaf Wetness sensor problems

I have the VP1 model and also a leaf wetness/soil moisture unit. Last spring the unit began to get stuck on a reading of 15 , so I did the usual checking of the unit, battery, sensor. Couldn’t figure it out, so I sent it to Davis with the repair fee, they fixed it and returned it.

About mid summer the problem came back and I got irritated, took it off line and stored it in the closet. A few days ago I pulled it out again and put it on the desk . I got a reading of — with no sensor and with the dry sensor an reading of 0 , this was encouraging. so I played with putting water on the sensor, the reading went up to 15 and then when it dried back to zero. I did this for a few days and then I did an inspection and it had no corrosion, the solar cell was generation power ( tested with ohm meter) , put in a new battery and installed it outside. It worked fine.

I get up yesterday and the thing is stuck on 15 and it is dry. First thought is some bird pooped on the sensor. So I go out and no bird pooped and the sensor is dry. I moved the plug to the second connection and got the same reading.

I checked the sensor for wire shorts and there are none. no breaks in the wires , etc…

I am guessing it is in the unit it self. So I removed the solar cell lead, the battery, and put it on position 4 to discharge the super cap and it finally did discharge yesterday and it shows — on the console as it should.

I am going to go back out as it is raining and hook the thing back up, and I am guessing I’ll get a reading of 15. In the winter it is nice because it shows frost.

Of course to replace the sensor would be difficult because no one sells the thing as it is discontinued and rare as hens teeth and right now I don’t want to purchase a VP2 just for this single sensor. The new soil moisture station that goes with the VP2 has the leaf wetness part of the station so one doesn’t have to have a separate item. However, again , it doesn’t warrant a new unit right now. I could order one, but why if the old one is functioning and it is a remote sensor. ( I know because it would bring in the new year, but I just bought the wife a new lap top and wireless network for her part of the house.)

The board inspection showed that there was no corrosion, loose wires, bugs etc. Looks fine, but I am thinking something is rotten in the state of Denmark ( or Iowa)…