Tail light - bang on lens cure?

So my passenger side tail light keeps going off and the bulb fail light comes on on the dash.
Fitted new bulb, raised copper prong in socket, socket is clean as a whistle/like new, all good, back on again although bulb I replaced looked ok …annoyingly, jarring speed bump at the mall parking lot extinguished bulb/put on BF on dash again this morning but a slight bang on the outer lens and hey presto, operation restored. Pain in the ass though, obviously some kind of loose connection in the rear quarter, plug to rear cluster clean and tight and indicators/brake work fine …any ideas lads?

It apparently is not an intermittent filament in the bulb, so maybe a dodgy solder joint on the board containing the bulb holders?

Thanks Mike, could indeed be that. I know I reflowed one of the boards a while back, (distant memory) …maybe it was the driver’s side one I did?

Anyway that will give me something to do next week - cataract surgery on Monday, so have to stay home for a few days after I guess.

Larry, before you start taking any parts off your car try another bulb. AND I know you have already replaced the bulb.
I had the same problem only a few weeks ago, I tested everything with my meter and could find nothing wrong with the supply to the bulb holder. I’d tested the new bulb before fitting and it checked out as fine, it was from a pack of four, they all checked out as ok with a test meter set to ohms showing a complete circuit across the filament but only one would actually light up when in position in the car.

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Well I took the rear cluster apart this afternoon and reflowed all the joints, haven’t been able to drive over to the auto parts place yet or anywhere else as still recovering from eye surgery …disappointing result on the reflow though, same symptom with bang cure…so will try another bulb in a day or so …what else could it be?
Doesn’t make sense to be something else ( :thinking: ) as all the bulbs in the cluster share the same three wires for power and ground - backup plus one stop/turn bulb are powered with one wire with tail and other stop/turn powered with the other. Common ground in the middle.

The turn signals and backup lights are ok …or at least I think they are …next time I get the bulb fail warning I’ll check the turn signal before banging on the outer lens :roll_eyes:

Larry, at the risk of stating the obvious, have you tried installing a bulb that is not working on one side into the other side to confirm or refute the bulb as faulty?

of course not! :laughing: …but guess what i’ll be doing tomorrow :thinking:

I tested all four bulbs from the pack I bought in the tail light cluster of my VW Golf, all four had shown continuity across the filaments using the ohms setting on my meter but only two of them would actually illuminate. The weird thing was only one of the two ‘working’ bulbs would then actually work in the Jag light cluster and it didn’t look the same, it looked a lot brighter than the other side. I ended up slinging all four bulbs in the bin and went out and bought replacements from a different shop and they all worked with no problems.

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New bulb fitted. Drove home and parked, no BFM so far, :slightly_smiling_face: :ok_hand:although same symptom as old bulb, sans bang on tail light.

We’ll see what tomorrow brings …usually BFM illuminates/bang cures :hammer: on first start of the day. :roll_eyes:

I had to use the bang technique a while back to get the driver side brake light to work. I would have to do this once in a while, but never got a bulb failure indication from the BFM. Upon looking at the bulb’s receptacle, I observed a fair amount of corrosion and assumed this was the issue. My tail light lenses were in need of replacement so before addressing the corrosion, I looked for replacement lenses. I found a used set that also included the entire assemblies. After replacing the assemblies with the new-to-me set, I no longer had any issues. So, although technically not confirmed, I’m sticking with the receptacle being the issue. I know you said yours are clean, and you get a BFM fail indication where I did not, but it still sounds like it could be the receptacle or its wiring to me.

No BFM when I started out today and purposely drove over some speed bumps faster than normal at the parking lot. Jarring the car like that has put that tail light warning on in the past, especially after returning to the car after shopping.
Made multiple stops and starts today, doctor’s office, shopping mall, friend’s house, recycle depot and even looked in on my fishing pals out at the lake. Speed bumps there too, again, the bumps had no effect …tentatively looks like it MIGHT have been an intermittently duff bulb as per @Casso’s call …hope so!! :crossed_fingers:

bulb still holdin’ …cured?

Hope so! And it sure sounds like it! I recommend visually checking for correct operation every so often for a little while longer. I offer this because in my case, the intermittent failure did not trigger a BFM warning. Granted, the root cause of my issue seems to be different than yours, but checking wouldn’t be much trouble.

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Cleaning contact corrosion
You said you reflowed solder check connector for corrosion… also remove bulb and check bottom spring it should be relatively shiny if not POLISH with pen erase or take regular eraser on pencil and wrap a thin band of say 600 sandpaper across and polish the lower bulb contact spring… sadly the JAG bulb holders are lackluster and not much tension on bulbs… ALSO and a great contact cleaner is called a SCRATCH BRUSH used to clean any corrosion traces before soldering. It is a small cheap brush available on AMAZON that has a pack of glass fibers in a bundle and boy does that clean metal surfaces fast…
Check bottom of bulb too for oxidized end… clean them too
Last minute… check bottom bulb spring connector for any looseness from say bad riveting or were these soldered too.

Best of luck
off topic…apologies
What cataract lens did you get for distance? I have cataract in R eye just appeared few months ago… was thinking multi focus but they claim some vision not clear… will probably go for distance…

Yes I cleaned everything up although in my car the sockets for the tail lights are very fresh and clean. Pretty sure it was the bulb that was the issue.

re: OT
Toric lens ($1100) to correct astigmatism, distance selected, vision now 20/20 in that eye and no glare from oncoming headlights. Only needed toric lens in right eye, left eye just going with regular distance lens. Vision is pin-sharp from about 2-3 ft to infinity, will need reading glasses or dollar store cheaters for the crossword/reading after left eye gets done, which incidentally will be in 3 weeks time (Nov 25th).

Hard to believe how bad my vision was prior to op, what I called my good eye before is not really good at all if I compare it to the new bionic one. Contrast/colour perception/sharpness/night vision so much better, can’t wait for other eye to be done, just 3 more weeks with the foggy yellow vision for me!
I thought about the multi-focus but ophthalmologist said there would be a fair chance I would still need glasses as there are no guarantees multi-focus works in all cases. Over the last year the cataracts progressed rapidly and just before I got my eye done the doc told me it was just in time as my vision had “fallen off a cliff” recently. Was not looking forward to winter’s twilight rush-hour drives in the rain with the blinding glare and halo-ing from those oncoming new headlights. Now, I think I’ll be OK. :wink: :partying_face: :sunglasses:

Glad it was just the bulb
And yes Ill probably get a distance lens too
“Vision is pin-sharp from about 2-3 ft to infinity,”

That’s great hope I can get similar results LEFT eye is AOK…

Bulb problem cured, left (other eye) getting bionicised Monday 23rd