I would suspect the Solenoid Driver Board. I had one with a socketed decoder chip (the big one) and the chip became unseated while I was working on it. When I put the board back in the machine all coils locked on.
Happy hunting!
cheers
Ian
+1
That would be my first guess.
I assume you have all the correct voltages out of the power supply board and you have 7 flashes on the Altek ?
Check J4 on the SD board . Maybe give the connector pins a light sand.
Can you remove the SD board from the Paragon to test ?
