You really should consider opening a support case even if it means paying time and material costs. The support representative should be able to help you with that. Anything else is just going to be trial and error on your part. If you truly have a bad controller then you'd need to source another one from somewhere and install it. If not done properly, you risk bringing the array down and/or data loss. So, it really depends how critical the system is to you and how valuable the data.
Sometimes an orderly shutdown of the system, reseating both controller modules, and bringing the system back up can do the trick but you'd need to schedule some hosts downtime to do this.
If you decide to replace the controller, instructions can be found here
