Hi Richard,
I haven't got an electronic copy handy, but having traced this out before in my own car, i'll describe it as best i'm able. The relay doesn't really play any part in the circuit, other than acting as a busbar....
Wiring for the cooling fan for the Cinq is as follows:
1/Battery +ve to cooling/headlamp relay (Furthest Left relay in fuse box) - this is one of the brown wires leading to the relay.
2/In the relay, this connects to an internal busbar which splits this feed between lights (via the switched contact of the relay) and the fan via a second non-switched (constantly powered) terminal.
3/This feed loops back out of the relay (the second brown wire) to feed fuse F3 (Bottom right fuse in fusebox).
4/Fuse F3 drives the fan via the Violet wire that runs to the fan motor.
5/Wire from fan motor (Dark grey/black coloured wire) goes to the fan switch/temperature sensor on the radiator.
6/Black wire from the temperature sensor goes to R/H front engine compartment earth stud.
Are you sure there's no power at all to the relay - if not, then you shouldn't be able to switch between main/dipped beam headlights, which suggests a broken cable/bad connection between battery and relay.
If you can still change between main & dipped headlights, then check wire between relay and fuse, and make sure that F3 hasn't blown.
Hope this helps,
Dan.
