Ignition switch & lock cylinder

[Gordie]

Went to start my 95' 530 but the key would only go into the ignition about a quarter of an inch. I figured it was a lock tumbler that had slipped. I was able to move the tumbler out of the way and get the key in completly, but now when I turn the key, I get nothing.

Does anyone know how the ignition lock and ignition switch interact??? Will a faulty lock affect the switch?? What initially seemed to be a lock issue now seems like a switch problem. Any way to test which may be the culprit???
Thanks

[shogun]

Here is a good (actually the only online) info how to remove the ignition lock.

maybe that helps