What Is DME Programming and When Does Your BMW Need It?

If you’ve ever had a BMW that wouldn’t start after a repair, or one that ran strangely after a component was replaced, there’s a good chance DME programming — or the lack of it — was involved. The DME (Digital Motor Electronics) is BMW’s engine control unit, and it’s one of the most misunderstood components in the car. Here’s what it does, when it needs to be programmed, and why getting this wrong can turn a routine repair into a very expensive problem.