This is the season (wet and cold) where the electrical grinches come out on my XK8. They are familiar visitors and I keep them at bay by trickle charging every night to keep the battery fully charged.

The other day I was driving home from work in the dark when I noticed a light gap on my left side. Pulling the car over i ran out front and indeed, my driver's side low (dipped) beam light was out. I put on the Main lights (high beams) and the driver's side was out on that one too.

I have checked the fuses (good)
Soft reset
Hard reset
Dried out the lenses (winter means they are always wet inside) with a hair dryer.

I have the cap off the headlight and the wires are all intact and connected well.

My small lamps function as well as my fog lights on the driver's side.

I am about to pull out the bulb element but I am concerned that both dipped and main beams are out on the same side at the same time.

I guess my question is how best to troubleshoot this problem? Is there a relay that works on only the driver's side? It seems odd that both main and dipped would fail at the same time (well...it's possible). I think I am looking for a common problem if there is one.

Thanks in advance.

RESOLVED: i tested with a multi-meter and had voltage at the bulb - Bulb itself had no continuity. Replaced the bulb and got both lights - high and low back. I used plenty of bulb grease as the bad bulb looked like it had moisture in it. The moisture lens problem was at fault.

 

The headlamp relays are in the engine compartment LH fusebox. R3 is for both mains and R5 is for both dips so, if one side is working, it can't be the relays.

As you have water ingress issues then a co-incidental failure of both main and dip bulbs should be eliminated first before looking for more complex causes.

Graham

 

Thank you Graham!!!