With due respect Craig, nearly all the Bosch codes start with 0231, it is the other set of numbers that come after are important. They are the ones that differentiate what the timing should be. If you look at the codes on the website you will see. So they are important. You can mark where the dizzy is with a bit of paint or marker, so you can line them up again to get it back to it's current position. loosen off the clamp, turn it round and get the full code.