I had the very same problem. When I got the camera on the workbench, I connected it to a variable power supply. I noticed that the camera charged ok until the voltage reached 6V. Then it just would not accept a charge. I then tested my panels (Rated at 5V) and found they were operating over 6V in full sun, which explained the charging problems I and other folk have had.
The cheapest solution I found was to solder a silicon diode (Type 1N4007 in my case) in series with the positive (red) lead from the solar panel. This involves cutting the solar panel’s cable, soldering and then covering the join with sleeving. Polarity of the diode is important with the white band on the device attached to the camera side of the cable. By doing this the voltage to the camera is reduced by 0.7V (to about 5.3V in my case) and the camera now charges in sunlight.
It’s not for everyone, but being a “techie” I had the tools and experience to be able to do it. Anyone who is able to solder and handle thin wires should be able to do it though.
Solar panels require direct sunlight to generate electricity. If there are obstructions such as trees, buildings, or shadows that block sunlight from reaching the solar panels, it can affect their charging capabilities. Additionally, extreme weather conditions like heavy cloud cover, rain, or snow may temporarily reduce the amount of sunlight available for charging.
I’ve covered a section of the after market panel with grey tape, maybe about 1/4, and it’s now charging in direct sunlight whereas before it only charged in the early morning or late evening. That kept the camera at 95% all the time but it wouldn’t go to 100%. My others were charged to 100% before connecting the panels and they have been at that level for a couple of weeks now, both in full sun.
Assess the capacity and output of the solar panels. Ensure that the panels are capable of generating enough power to meet the charging requirements of the 2C cameras. If the panels are undersized or not providing sufficient power, it may result in slow or ineffective charging.
I’ve only owned the S340 for a week. Only in the last couple of days, I noticed that the battery level was going down over 7 days though I had the camera with the extended solar panel wiring (where the daylight was better). I tried all various permutations of phone app control but was not able to see any recognition of the solar panel. Just when I was about to give up, I had an epiphany and it worked !! What I did was to carefully clean the contacts on the solar panel cable…both at the short cable stub exiting the solar panel, as well as the extension cable ends. I also made sure that the cable ends were FIRMLY pressed into the female socket. In my case, that did the trick (happy dance) as I was rewarded with the phone app animated battery symbol for the S340.
It’s possible that the contacts were oxidized or whatnot. What i used was the electronics favorite “deoxIT” which cleans and preps the contacts for a better connection. You may want to see if a tech DIY friend already has this to save you from having to purchase this. Or, you can carefully scrape the cable male ends and use something like auto contact/brake cleaner. which you may already have in your garage.