RH Headlamp failure X150

[jhharrington57]

I thought i would share with others a problem I had with the RH (offside) headlight, both dip and main on my 2007 XK. All other lights within the RH headlamp unit, and also the RH foglight worked normally. Bulb and ballast unit change made no difference - the headlight still did not work. I eventually traced the problem to a poor earth connection. On the right hand side, the earthing point for the headlamp unit is in a very exposed open position in the wheel arch. Rerouting the earth to the nearest earth point within the engine compartment solved the problem. The wiring on the nearside (LH) is different, and no such exposed earthing point exists there. Frustratingly from a diagnostic point of view, the earth was clearly good enough for the other bulbs. I hope this information to those who may be experiencing problems with the RH headlight.

[mike020150]

Thanks, that's a useful tip for all we X150 owners. Mike.

[garagedood]

This presented as a failed front right indicator on my 2008 convertible when I brought it out of hibernation last spring.
The fault was annoyingly intermittent and checking revealed that the bulbs in the light cluster and the side repeater (both apparently failed ) were fine.
When removing the nut to clean up the earth it sheared off revealing only a tiny bit of shiny metal in the centre - clearly the culprit.
My guess for varying symptoms ( for some head, for others indicator lights) from a single cause are that as there are 2 terminals carrying 3 earths between them and one or two of these might be getting sufficient ground to function but not the other (s).
My solution was to drill out and tap the remaining stud and after cleaning the O terminals used a suitable alloy bolt to fasten them back up in the original location, slightly awkward with the suspension leg being in the way but do-able without any dismantling other than taking the wheel off.
The finished job looks little different to when the car came off the line.
If you are not a tool guy and don't want to tackle it yourself it might be worth getting the garage to do some preventative maintenance in this area - undo the nut, clean it all up and protect against corrosion before reconnecting - next time it is in for service. Cost should be negligible as the car will be up in the air with the wheels off anyway.
I have a feeling this will become a common problem as these cars age but fortunately is easily rectified.