I have taken the cowling off to get to the indicator / light switch. When exposed I can hear the relay on the switch clicking when i play with the white relays in the fuse box.

I have checked all fuses in the fuse box and also the bulbs and all are good.

I assume that the problem surely lies with either the white relays or the relay on the back of the switch. I have some spare white relays and have tried them - no difference !

I am waiting for a switch relay to turn up so cant test that yet but apart from that I cant see what else it can be - given that neither o/s or n/s work i guess its not the white relays as there is one for each side of the car - the only item that controls both lights at once is the switch / switch relay - hopefully this will solve the problem