Ignition coil not firing on one side but coil appears to be good

[Newbiescott]

 Idled my '93 today and started pulling the plug wires while it ran..... pulled the RH cylinder and it made absolutely NO difference to the sound or RPM.  then I pulled the LH plug wire by itself and the motor stopped abruptly !  Ergo my bike is running only on one cylinder !! hooray
So I shut it down and switched the good LH coil for the (thought to be bad) RH coil to check out if the RH cylinder would fire.
Made the switch and now the LH cylinder starts and fires using the RH ignition coil.  But the LH coil now in the RH cylinder does not fire at all.
So my brother checked out both coils with his OHM meter and found that both tested well within the specs from my Haynes manual.
So it appears that the wires feeding on the RH cylinder for power to the ignition coil are not working.
After checking the wiring diagram in my manual I see that both coils share the same Hot or positive lead but have their own negative lead for appropriate firing order I'm guessing.....
I traced the wires and they all go back to this large plastic block which is the ignition brain I assume....

Does anyone have any thoughts or input because with this ignition block I will call it I am out of my league !!!

thanks Scott

[gsJack]

Could be the rt side pickup coil causing the problem, there are 2 pickups under the little round 3 bolt cover at the right side of the crankshaft.  Also check the plug wires to make sure they are tight in the coils, they are screwed in and bonded tight and won't turn or pull out if OK.

[lucas]

yeah so it sounds like your coils are good.  Check the signal generator sensors next.

[sledge]

Look at the battery negative connections, there is a large one and smaller one. The smaller one is the return for the ignition control module, if the connection is poor or broken all sorts of weird shaZam! happens.

Take it off, clean it, remake it if you have to and then retighten it.

[Newbiescott]

Thanks guys you have given me some good leads !!!!!!

I will try them out later this week 😉