All fixed. New resistor, diode's and a transistor. Target reset now works great. Even seems a bit more powerful than before.
I replaced the diode on the solenoid it actually fell apart as I removed it so I'm thinking that was the course from the start and the solenoid board Copt the brunt of the failing diode.
Thanks heaps aussiepinball again. And big thanks to pinnies4me.
