Bathroom Light Fiting ?

I have a light fitting 12v, integeral transformer with a blue and brown wire, a pull switch and 12v bathroom fan. I have three cables 2 wth red black and earth cables and another with a blue, yellow (with a red bit of tape on it) and earth cable. I can get the power to the light but itstays on and cannot be worked with the pull switch. Would you please show me the sequence of cables to be joined together?