Technical New daylight running bulb holder melted

[spleenharvester]

About three months ago I replaced all four OEM headlight fittings on our 2011 model due to the mounts having been knackered by a few minor crashes. We changed all the bulbs at the same time, in the DRLs we used Bosch W21/5W (580) bulbs. Today we start the car and are greeted with a check daytime running lights message, and sure enough the left side DRL was out. I found this a bit odd as (a) it's a new bulb and fitting, (b) the plastic around the DRL holder has melted and deformed, and (c) there's nothing wrong with the bulb visibly, no broken filament, it just won't light up.

Fortunately the contacts look OK and the bulb still holds in place so I replaced it with another Bosch W21/5W 580, it lights up OK but I did notice the bulb gets hot very quickly after the car is turned on (like within 10 seconds or so). Left the car idling for an hour and it's still OK.

Just want a sense check is this definitely the right bulb for the car? My first thought was crappy aftermarket fitting but the contacts look fine, albeit with a bit of heat discolouration

 

[steveras57]

I have noticed myself that the holder does get extremely hot -I would guess that over time the constant heat cycle breaks down and weakens the plastic as yours is the same age as mine.
In the end i just changed the whole D R L lamp for an aftermarket replacement for about £60 still gets hot but has not broken down after a years use! I also use OSRAM bulbs which seem to last the longest.

 

[A3jeroen]

21W gets hot no matter what type of bulb. I always drive with my dipped headlights on, so only the 5W gets used and no problems (yet).

gr J