How to identify a relay anyway ?
There are two or three methods or more :
1- the clicking coming from inside the relay when you operate a switch.
2- the Work Shop Manual on section M10 lists several relays but I have to say that it lacks precision and does not always match your particular case
3- the colours of the wirings to which the relay is connected : note them and refer to the theoretical diagram that matches your car (again there may be some difference with your particular case)
For example on the picture you notice a dirty Blue-Yellow plastic wiring which suggests according to the Lucas colour codes a link to the headlampSource: Diverse