Environment Error: μC2 maximum supply voltage exceeded

What does 3 mean?

When LED Diag 1 is off and LED Diag 2 flashes with code 3 (400ms ON / 400ms OFF), it indicates that the internal supply voltage for microcontroller μC2 has exceeded its maximum permissible limit. This environment error suggests an overvoltage condition, carrying a risk of damage to μC2 or other internal components due to excessive electrical input.