80 HP 912UL will not start

Sounds like it's time to share...

I think a collaborative effort is needed to resolve this expensive problem.

I have done some work already but run out of time to do any more at the moment.

Here is a link to some of the information that I have:

Rotax Ignition Module Files

If the back of the case is being opened up to replace components then it is the SMT parts mounted on the back of the board. If someone knows the location then the the photos that I took of the back of the board will show the likely candidates.

I took all of the caps off and measured them on a bridge so I know the values. I don't know the voltage ratings but the package size is a reasonable guide. The BOM contains my best guess at some of the parts. The FN indicates a Farnell Components part number.

If anyone needs any further info I have CAD files in Proteus format but I can create Gerber files for the layout if someone wants to make a new board. I have found a cheap source of the connectors if they are needed too.

De-potting the whole board is very time consuming but using something like a Dremell to cut a window in the case and then just remove the potting from that area is far more practical. The components can then be replaced and the hole repotted to finish the job. Given the nature of the repair it needs to be done by someone who has worked on SMT boards otherwise the repair will not be reliable.

I have suitable equipment at work and I am happy to replace components if someone can identify what needs to be changed. I can carry out the work for free on the understanding that the unit is to be used for test purposes only.

Kevin