Hey Mert! I’ve fixed a couple of overcharging systems with this problem and it was a poor grounding set up both times. The stock regulators drain the overvoltage to the ground (as opposed to the mosfet smart system) and when the regulator ground fails the excess can blow headlights and melt batteries. I’d bet the ground has built up corrosion that’s reduced the capability to drain the excess properly. The mosfet systems are a better design, though, so it would be an improvement.
