Sorry to take so long answering.
This is not an involved question but the answer takes some thought and time because this was the early part of my search.
First off my board wasn't bad it was a bad ground. The question I would ask you now is do you have the electrical schematics for the A1?? The schematics show you that there is only one or two grounds on the board (if I remember right) and they or it are grounded at TB2 I think and that is a ground strip and can be seen easily if you pull your whole board out of you distribution panel area. (I am working off of memory and may not be exactly right but be kind, the schematics tell all) Once you see the ground strip it is pretty easy to work with.
Now ultimately my problem was in my Transmission Keyboard, can't quite explain why the symptoms showed up as they did but that was my solution. By all indication it was a bad ground and not working the neutral start relay.
On my turn signals it turn out to be my solid state flasher and again the symptoms indicated something else but I replaced it with a mechanical flasher and that resolved my problems and with a schematic you can get the wiring to hook up to the flasher. That is quite easy because one is a ground, one is a load, and one is 12 volt supply.
The horn was bad connections at the horn and if I recall correctly it was removed and mounting cleaned thus establishing a good ground.
Don't be quick to condemn the board. It is expensive and not exactly a dime store item.
If you don't have a schematic let me know and I will supply you one.
If this didn't answer your question please get back to me.