Clicking noise when I switch the side lights on.

When I switch the side lights on I get a fast and quite loud clicking noise that comes fron behind the front near side light cluster, it only started today.
All the lights work fine. It is there with the ignitation both on and off. When I lift the bonnet it seems to be coming from below the air filter box.

it must be from the headlamp levelling motor, it turns on and off together with the head/side lamps... if it's pre-facelift you can remove the inspecting cover to see it... probably the connection to the lamp is cracked or somtething

Thank you, you are right, when I move the headlight balance switch the noise does change.