12v (input) issues

Four coils model with L36/L36A - L37/L37A,

Four coils model with L36/111 - L37/222,

Two coils (old) model with L36 - L37, (C) Forhike

12 volts places,

Or,

12v shorting on the pcb, Most defective spots.
Most defective spot is the C312, C313, or C314.
Best is to remove them, measure by Ohm if it's solved.
If not, do the same at the other spots.

Why, they all are connected between 12v to ground.
If one of them is shorted.. Then you have shorting.

Howto measure short circuit (Ohm measurement).

New drawing, in this you can see all the connections to the 12v circuit.

(Thank you to Johnny_B for publishing it)

All the best about hardware/support from Johnny_B, link :
http://jb8a8f8.com
http://jb8a8f8.nl

More