using a 150/70 charger, worked fine for a year, now just stopped. disconnected the negs, then reconnected, charger shows bulk charging but it is not passing the charge through from the 4 200 watt solar panels. 12.5 volts are coming in from panels, nothing going out. any ideas? remote location with no connectivity.
Sounds like you have a bad connection between your panels and mppt.
Check the wiring and all connections.