The passenger headlight bulb is constantly blowing say ever 3 months. All other bulbs are fine in fact they have never blown since I have owned the car just this damn left side one. I always buy quality bulbs never touch the bulb so maybe a wiring problem somewhere or is there a fuse I could check replace. The car is mk2 face-lift focus. As said all other bulbs never blown and not starting to bug the hell out of me.
Usually it can be figured out by looking carefully at the bulb/lens/filament.
But without that check the actual bulb wiring connector.
Is it heat damaged?
Are the terminals good and tight with no discolouration?
But back to my original point,
Is there any colour on the lens
Or is the filament broken off inside?
Careful observation needed here!
Seems a bit silly now I think about it but I usually just bin the old bulbs but memory does tell me that the filament is like a white ish colour like too hot so I guess too much juice is getting to it at random times. The connection to the headlight unit is solid but only the head light fixing itself the locking clip has a bit missing but it doesn't really move. Again from what I remember the headlight bulb holder has 4 wires attached and I believe 2 are resistor wires so maybe these playing up maybe?? Cheers.