I recently had a failure in one of my Rotax Electronic Modules which of course meant I was running on 4 plugs instead of 8. I was able to switch the input to the modules and the problem changed. I then switched the output and found no change. It wasn't difficult then to isolate the B module. All three Rotax dealers were helpful but only one had the item on hand which they shipped today. Be sure to register your Rotax to have a chance at warranty compensation...they look that up on the computer when you first call. They send a warranty packet for you to fill out and return with the module. It goes to Canada where Rotax has a bench to test your claim. Once varified, they send you a check. Meanwhile you can purchase a new part and take your chance that its varified or your can wait....depends on how confident you are on your troubleshooting. Unfortunately, the modules are Ducati which made the same regulator that blew up on me...hmmmmm. I still love the airplane and engine and would never let this change my mind...lord knows how much money I spent on Lycomings....and they never got 4 gph on car gas.