If it restarted the sequence the tach would go back and forth every single time. It’s not a sequence, it’s a computer program. And it has to go through several steps before it completes. These are very small voltages inside that computer with millions of calculations happening. If there was a short in that itself, it would never run. It’s not the same as the 12 volt system it controls. Now one of the sensors that it’s reading could be faulty, maybe a short, or maybe just old, or has a production problem. It could be the tach servo itself that has a problem determining its limits. Lots of things it could be. But it could also be exactly how it’s supposed to be.