well i'm sure if the cap goes bad or is starting to fail it could cause what would seem to be PMT.
If it doesn't charge up correctly it can't fire the 1REC circuit properly and would cause the system to fail.

Unfortunately for the EV100 system they are very voltage sensitive so any component that does not get the proper voltage can cause problems. Some of the most common issues with these panels is the 1, 2, 5 RECs and i have seen a cap or two go bad in my day :o)

The fun troubleshooting ventures on these is when you have a reactor or a spider block go bad...
talk about a troubleshooting pinpointing headache... ugggh