I have been commissioned to repair the electronic module of a failed ignition control unit of a 1979 BMW 635CSI short stroke. The control unit “025” is not unknown to me. In 2001 I converted one of these otherwise flawless electronics in my own vehicle using modern semiconductor technology. I managed to achieve about 30% more spark energy at 6000 rpm compared to the factory module, without any significant warm-up. The control unit has worked flawlessly until the final delivery in 2019. I did not repair the faulty module that just arrived, but combined the control developed in 2001 with the ignition transformer control stage used in my engine control system to create a new electronics. In keeping with the quality of the workmanship, I have given a perpetual guarantee on the finished product.