So I removed the starter and the mating service/ lug were filthy, however after a good clean still no luck getting the car to fire. I went back into Vida to do the fault trace and this time I figured out a bit more of how the software works. So I found the link in fault trace that takes you to the guide to replacing the rpm sensor! Didn’t realise Vida did all that as well! Awesome bit of software.
It appears the EGR mixer needs to be removed to gain access to the rpm sensor? I’ve attached the image from Vida. That process looks a bit of a pig as says to drain fluid and replace gaskets, is it possible to get to the connector to the sensor without going through that?
The fault is also specifically ‘faulty signal’ not ‘signal missing’ and advices either poor connection or oxidation of parts just as you were saying. I am much happier with how I’ve fitted the starter motor though now
