External Solar PIR Lighting Question?

[saltyseadog]

Around two years ago I put up three PIR solar powered lights outside. They worked fine but this year I noticed that they weren't coming on anymore. Unplugged them from the seperate solar panels and on checking them I found them all watertight with no signs of rust etc at all. On checking with my multimeter I found all the rechargeable batteries pretty low though so bought new ones of the same spec. Put the new batteries in and they worked on both auto and PIR settings on all three lights. Remounted them outside and reconnected the panel, set them all to PIR and thought jobs a goodun until I checked that night only to find them still not working. Took them down and checked that the new batteries were all still in place but noticed that when they were disconnected from the solar panel they worked okay. I then took the solar panels down and checked them but found no obvious problems so gave them a wipe with a warm soapy cloth and remounted them again. That night still not working on PIR or auto. If I unplug them from the panel they work as intended but stop when plugged back into the panel. Now if it was only one of them I would assume a faulty panel but it seems strange for all three to have the same fault at the same time. Thought I should ask at the forums here to see if I am missing something simple?.

[Someone-Else]

If the lights work without the solar panel, but do NOT work with the solar panel then it must be...........the solar panels.
Do you get any voltage from any of the solar panels?

Bear in mind that most solar lights last around 2 years at most, then you have to throw them away, the idea being the maker gets more money when you have to buy more lights. In general solar lights are a good idea, but are just a waste of money as they often have cheap solar panels that fail. I have seen several attempts to save said panels. (Clean the panel, put sticky tape over it, use sealant) none work.