My 2001MY Zetec has developed a strange Electrical fault.

Drove off everything was fine, went to use the indicators they had stopped working also the
heater fan
electric windows
Horn
All had stopped at the same time but the engine runs OK and all the electrical switches appear to work OK

All dash waning lights come on with ignition on, after starting engine they all go off in the normal sequence.

Started at the obvious, the fuses and they are all OK.

I'm not getting any feed to the heater switch etc. I'm thinking it might be the ignition switch. 4 wires on the back of the ignition, 3 have a feed. The 4th black with blue tracer no feed, is this right??

I can't seem to find an ignition switch diagram any idea?? or has anyone else had this problem and know the fix. Thanks