So my 2018 facelift L405 left hand headlight stopped working a few weeks ago. My garage (not official RR) told me it needed a new headlight. Managed to get one from Charles Trent second hand (brand new over 4k!). New headlight installed, but car will not start. Engine turns and occasionally catches but then dies. Garage has no idea. HELP! ...

disconnect the newly installed replacement headlight and see if it starts...if it does then its the headlight thats causing the problem..

if it doesnt start then you've caused this problem with the install... ... - .- -.




Y. O. L. O.
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I don't know which garage for now doesn't have diagnostic tool, even basic one to read pcm only. It will let you know where to start from. As Stan said plug it off to see if it causing some can bus issues then dig it further. But garage has to know basics like this even not RR specialist.