Hi,
I have had similar problems on a boat.
2x 80w panels 12v were giving 8amps in sunny France.
Then for no apparent reason they stopped charging.
Tried 2 different charge controllers and still no charge.
This was 18 months ago.
Our batteries were getting old almost 8 years. 4 x 160ah agm.
New batteries fitted and suddenly the batteries are being charged by the solar panels.
No other changes to wiring etc. made.
So if you have old batteries (ours after charging via battery charger were showing 12.6v) and your solar panels are not working, think about new batteries.
It worked for us.
