Hi - This evening my passenger side headlight bulb became incredibly dim while I was driving - Passer-by notified me as such.

When I got home I got my new pack of bulbs and fitted them in - I connected up the bulb to the passenger side and before I re-fit it I did a quick check. From how it was angled it looks like it was perfectly bright and therefor fixed - I put it back into position and worked on the driver side.

When both were fit that's when I noticed there was absolutely no change at all, the brand new bulb was working but still very dim. I am not mechanically minded it is fair to say but I did run through some troubleshooting to be sure!

First I disconnected the passenger side - Driver side still absolutely fine. I reconnected driver side and unplugged passenger side. At this point BOTH lights stopped working entirely until I reconnected the passenger side.

At each time when I would turn off the ignition, there would be a mechanical clicking noise/whirring. The only time I have ever heard this noise before is when I have had a dead battery and had no electrics at all through the car.

Full beam works from what I seen, fog lights also.

I have my MOT next week typically so what a time for this to happen. I don't know anything really about fuses but that was my next line of enquiry.

The image provided isn't very clear - The passenger side looks bright but it actually isn't but you can tell there is a difference in brightness.

Fuses either work or they don't. If the fuse is blown you wouldn't have a headlight at all.

The best thing I can advise is to narrow the fault down. Luckily you have a whole working side to borrow bits from. First take the lamps out of the holder and test them side by side. If they both look the same brightness then try plugging the drivers side light into the passenger side and see if the dim light swaps sides too. If so you know its a problem with the reflector unit.

Sounds like a dodgy earth connection to me ??

I suggest it’s a poor earth issue look around for a rusty bolt with wires attached under the bonnet 

I can look for that yes. I did see a video about the earth wire. Should I be looking in the vicinity of the battery?

Also I wonder - Could the cable attached to the light housing cause this perhaps? I have obviously reseated it several times but it was dark last night so I didn't really have time to look at the connections

Check the earth is clean and tight on the battery but it’s likely that it will be an earth bolt near the lights corroded with the weather etc so see if you can see it.otherwise find the earth wire coming from the lights with a multi meter and re route a new piece direct to the battery hopefully that would fix the issue if it is an earth fault 👍

Hi there! Bit of a strange one but I went out just before dark this afternoon. My left indicator light started clicking really quickly so I took that as a sign that this bulb also was about to pop.

When I got home I fit the indicator bulb... But before I did I tried re-seating the cable to the headlamp. I wasn't as rushed this evening as the rain stopped and it was quite light still..

The main headlight came on perfect... So I wonder if I knocked something (Loose wire?) or made sure connection was much more secure - Sure enough it worked. Replacement indicator light soon followed which fixed that issue separate. Whether there is still an underlying issue I don't know mind.

Looks like you’ve found the issue 

leave well alone now 😂😂😂