L = Low (10 V to 11.9 V)
I = Intermediary (12 V to 14 V)
H = High (14.1 V to 16 V)
You need to adjust for your needs of levels
I try to adjust but here in EC not work like in reality, I built it and work nice with some values changed
Adjust zenners and resistors from digital display only
Transistors: 3 x BC177 or BC178
Power source: replace with your car 12 V battery!
