Yamaha 85AET

Hello i own a yamaha 85 AET. Does any one know the year of this engine? Also one day my outboard took about 1 hour to start and after heating the plugs cleaning the carb it eventually started and ran for about 5 minutes at about 3000rpm which is when it stopped and wouldnt start again. However the next day i went to stat it and it started and then cut out about 20 seconds later. The fuel is fine but there is no spark on any of the three cylinders. I have checked the key all was fine and i also have checked the killswitch which was fine. I still cannot find what is the problem there is a fuse on the outboard which is fine. Is there any specific wire i should check?

Thanks.

[boats.net]

You can disconnect the white wire(ignition stop circuit) from CDI box to eliminate wire harness and ignition switch. Engine will not shut off with wire disconnected.

Thanks i will try that tomorrow. If it is not that then what would need replacing?

[boats.net]

Then need to test ignition componets on engine to find failed part.