Afternoon all, I have recently started using WIS, and without the benefit of the no doubt lengthy dealer/manufacturer training courses, it is of course a daunting tool to get into and start using. I am trying to diagnose intermittent only working in my car's ('09 S211) rear ambient, and dome lighting. So, I search WIS trying to find wiring diagrams for my VIN. The best I can do is the following wiring diagram, which shows the relevant lights (E15/3) being controlled by N70 - Overhead Control Panel Control Unit. WIS Int Light Wiring by MJJ posted Feb 14, 2020 at 12:23 PM I am then trying to find where that is located in the car, whether it just means the light unit itself, and whether that N70 OCPCP is ultimately controlled by one of the SAMs in the car. I cannot get any further useful documents to help find locations, or wiring diagram to the N70 OCPCP. Any tips from WIS users on how you would go about trying to do this sort of diagnosis? Would you keyword search, navigate the various tree structures to try and find a diagnosis document, maybe look for block schematics rather than wiring diagrams? Thanks for any tips people can offer, Martin.