Problem(s) Encountered:

When closing the MIS hatch at the end of the night it was noticed that a small belt with around toothed wheels was about to break (or more accurately, a previous repair to this belt was about to fail. The belt is on the MIS finder unit, above a component labelled 160.

Solutions:

We replaced the belt for the Finder mirror (retrocam mirror) and tested the system, all works fine.