Evening all,

Due to weather I thought time to run the L405 Supercharged out.

So here's what's happened, need some friendly advice. (It will go to dealer tomorrow, but wonder if anyone else has had any similar issues?) By the way perfect main dealer service history and never missed a beat and always serviced early or on time and always ran on super unleaded.

Driving on M25 with adaptive cruise on, headlights on automatic on and then all of a sudden.

Drivers side headlamp failed, engine dropped to restricted mode and every Yellow & Red warning light (I mean everything) on the dash came on a scrolled through every warning, steering went heavy and went into limp mode with restricted performance. Right hand indicator flashes real quick like bulb gone. Left hand indicator ok. Strange thing was rev counter working, No speedo, just sat at zero??

Did the normal, pulled over, stopped, drivers headlight completely dead, no indicator, no drl no headlight no side light no main beam. nearside works perfect.

Locked car, waited for car to power down completely and then unlocked and restarted, no change a whole host of bongs, and warnings engine ran fine but again restricted performance and steering reasonably heavy, a bit of power assistance but not perfect. No puddles of anything below other than my pride!

No idea how fast i could go but I certainly annoyed a few lorries, at I reckon around 40mph max speed. manual box wouldn't work so it just sat in drive.

So my theory is headlight has blown up and caused an electrical fault but I am not sure???

The car is standard and not messed around with in any way, the bumer is Warranty is expired so sounds like could be expensive.

If i can work out how to upload a video I will.

Any thoughts please or words of wisdom, other than use the other one!!

I look forward to wisdom of the forum.

Sounds like a ground stud connection issue, probably in one of the wheelarches behind the liner.

Ahh, had a similar issue with my Discovery 4 earth strap corroded and everything went haywire!!

I assume that would play havoc with everything including steering and every warning, but explain why engine runs fine?

Last edited by DrF on 24th Jan 2023 8:59pm. Edited 1 time in total

Any idea how i upload a video ?? Quite spooky the result

You need to sell your soul to Google (other parasites are available) and link to it, you can't upload directly.

Thanks, I will have a go?

Could this be the issue?

Click image to enlarge

Click image to enlarge

Without 'hands on', yes, that would be a good starting point. reading DTC's won't tell you much as there will be an overwhelming number of 'me too' DTC's, the key is to find the ground point for the headlight and go from there. The headlight is the only physical failure, finding the cause of that will resolve the other cascade issues.

The reason I say check the ground point is that everything on the headlight is non-functional, clearly all the various lighting circuits rely on a single ground - also a single point of failure for other circuits using the sasme ground point.

Thanks, thats a great start

Thanks Mikey

The main dealer reckoned it might be this too. ANd my fingers crossed

I will keep you posted.

Mikey wrote:

Click image to enlarge

One on each side, behind the arch liner

looks like jlr's topix app..

you will have to be a service garage to access that.

we do have WM's in our wiki .. ... - .- -.




Y. O. L. O.
.

Paid for access

Can be purchased by the hour/day/week/month etc

Good news, seems like earth connection failure in wheel arch as diagnosed by MD and forum fellows