As said previously start with the fuse is it correctly rated and working. As the kit might have been non Morgan installed check to see if there is an override switch installed somewhere in the cockpit. Also check to make sure fan is working by connecting directly to battery, if it is then trace the wiring back to see if there are any breaks, etc.. If all checks out then it is probably the ECU connection or software not updated. If it is a software issue then a chat with a Morgan dealer will probably be able to resolve that as they will still most likely have the update.