I concure with Sprokets first suggestion, try swapping the bulbs over. If the fault moves with the bulb, then the bulb is faulty, But I doubt the switch of wiring is faulty as the filament bulb works.Sproket said:Have you tried it in the other lamp fitting & tried the good one in the faulty fitting ????
It could be that the swich is not working or .......![]()
Possible broken wire or loose connection on the back of the lamp fitting......![]()
You will have to remove the fitting & check the connections with a multimeter, you could have power to the connections but the switch might be faulty![]()