I got a low ISS battery note last summer, so I put in a new battery and went on. Earlier this month I came home and saw the outside sensors dashed out. So I hoof out, take off the cover and flip the test switch up and no led light. I put in a new battery and it flashes like mad. So put everything back and figured it was a bad super cap. I didn’t have time to fiddle with replacing the cap so I ordered a new board from Archer Trading. They sent the board, antenna and case, all I had to do is go out, take off the ISS, fish the cables in and out of the abnormally small access area . I finished as the sun was setting, so I put back in the battery to run over night the next day, I went out and put in a fresh battery and we are done.
When the weather gets better go out and take off the solar panel, and unscrew (phillips head) the four screws under the plastic dome that hides the components and look at the supercap to see if it is leaking or not. If it is, then you could order a new supercap and have it ready to replace when you have the chance.
I am thinking that since Davis has a video on their support site on how to remove this unit and replace it, the death of the supercap is more prevalent than we suspect. In the instructions on replacing it , the warning that the leads must be bent away from the bottom of the supercap case and that looking at the picture attached it isn’t. Then Davis recommends putting in a spacer between the replacement supercap and the circuit board to take a strain off the base, indicates to me that they have a quality control problem when the boards are made.
In any case, now I have two ISS boards, ordered the supercap from Archer Trading post, it has been shipped and on their site they have the same recommendation to protect the supercap http://www.archertradingpost.com/atp/index.php?main_page=product_info&cPath=1_6_9&products_id=68
