I'll try to listen to the sound video later.. can't open it where I am...
but if it's coming from the headlamp then it's almost certainly the adjuster motor. There's a little motor in there like from a Scalextric slot-racing car.. it turns a small nylon wheel that winds a lever out that pushes the reflector down, or pulls it up.
If any of that goes wrong (e.g. if the nylon wheel spindle seizes up or it strips its teeth) then the motor will keep turning, until it eventually burns out and stops buzzing.
You'll need new motors; since last May the headlamp adjusters became an MOT test item, so they have to now work, even if the beams are not dazzling anyone.
Good news is that the motors are only aboot £8 each on the Bay of Fleas.
Bad news is that it's a bumper- and headlights-off job to change them.. (don't let anyone fool you that it can be done with the headlamp in place.... you need a trained Capuchin monkey with double-jointed elbows for that). It's *possible* but you'll be there 4 hours and swear a lot. Have a go by all means.. then take the bumper off..
Removing the bumper is not difficult in itself.. you just need to take your time, remove the wheel arch liners, undo all the bumper bolts (two at each front wing, which may be Torx heads... and a couple or three under the radiator). Then you have to unbolt the bumper supports under the headlamps (two bolts each) and then finally the headlamps - three bolts each.
It's *much* easier and you'll be able to see how it all fits together with the headlamps on your kitchen table.
The motors have a rod with a nipple on the end.. this fits into a groove on the back of the reflector. Unclip the tiny electrical (tab) connector and unscrew the motor (2 small screws) and then slide/rotate the nipple out of the groove. The new ones go in the same way.
The reflector might move when you take the old one out and the new motor nipple won't then reach the groove.. so use your Capuchin to press the reflector down at one end, so the groove moves towards the nipple. Slot it in (it rotates slightly as it goes in) and screw it in place... then re-connect the connector.
While you have the lights out.. replace ALL the bulbs.. since this is a brilliant opportunity - and you already saw how much space there is behind the lamps when they're in the car...
And make sure the dust covers are fixed correctly.
I would replace BOTH motors at the same time. They're c.15 years old now.. and if one has gone, the other can't be in much better shape. It may even be not working already and you've got away with it since the MOT changes, if your last tester didn't remember the new stuff and forgot to test it. For the trouble you need to go to, when you have to change it later, it makes sense to spend an extra £8 now.
Ralf S.
