nellytruck

I have an extractor fan with timer (for my bathroom) that i want to operate from a (separate) pull cord. I am about to fit the isolation outside the room. The wiring diagram that came with the fan is to connect via the light. As I want the fan to be independent from the light (the switch is outside the room) how do I go about wiring the fan to pull cord switch to isolating switch? Can someone advise, please...?