2000 Jaguar S type

You need to drop the front bumper. This is quite involved, from memory 2 large bolts on the topside, couple on each side, in the fender (need to remove plastic wheel arch liners) and about a dozen small bolts on the underside, that hold the plastic cover that is under the engine. Then 3 more bolts to remove each light. Oh and be very careful not to break the adjuster tabs when putting new bulbs in. The clip is fiddly but can be done without all this dicking around. Get a small mirror such as that used for dental work, and a flashlight, and see what the problem is. The fiddly little bits they put on cars can drive you insane.