Have an operating entry level Alaska GP9 that when received was missing PCB reversing unit (likely died) and wired for forward. Picked the R.U. up in Lionel parts sale. As this is not a switch and replace operation, I have no idea on how to wire other than trial and error. I would appreciate help from members via pics. of wires and/or their guidance as to where wires might attach to on the R.U - there are 4 different pin locations on the PCB that can accept wires - J1, J2, J3, J4.
On the reversing unit, J1 is a 4 pin, and J2 is a 5 pin, and J3 and J4 are both 2 pin. The diesel revving sound currently works as does the horn and bell and volume knob so the sound/secondary PCB on the engine frame seems to work. It was likely never disconnected. However, 2 yellow wires coming up through the base in area of volume button are not attached to anything. No crew talk (if any) so maybe those wires need to be connected to something.
Bottom line - keen to at least get the engine to reverse and anything else is gravy.
Thank you in advance.
