tail lights with LED's

PostPost by: bill griffiths » Sun May 14, 2017 11:30 am

I recently purchased LED globes for my replacement Plus 2 which will be like new and is now progressing quite quickly.
I discovered however that the globes I chose emit quite a bit of extraneous light to the extent that when the
tail lights are lit, let alone the brake lights, the amber indicator lens is also illuminated.
I think the fix is to insert a thin strip of card, or perhaps aluminium, horizontally between the tail light/stop
lens and the indicator lens, held there perhaps with a dab of silicon, before replacing the tail light glass.
The display otherwise might be confusing to those behind....and in our cars there are usually plenty of them!
Regards,
Bill
bill griffiths
Second Gear
Second Gear
 
Posts: 171
Joined: 22 May 2007

PostPost by: The Veg » Sun May 14, 2017 12:54 pm

Sounds reasonable Bill; show us a picture when you get it done.
1970 Elan Plus 2 (not S) 50/2036
2012 BMW R1200GS
"It just wouldn't be a complete day if I didn't forget something!" -Me
User avatar
The Veg
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2329
Joined: 16 Nov 2015

PostPost by: bill griffiths » Wed May 24, 2017 3:00 am

Some Plus 2 tail lights were actually fitted with a divider, riveted in place.
The lights which came with my boxes of parts did not. However I found a pattern and I shall attach a picture.
The original divider was made of panel steel but with LEDs and no heat I used light aluminium.
For the first on I cut up a beer can, and for the second I used a coke can.
I think the coke can was marginally stiffer!
I painted both sides of each with etch primer, bent the tabs at right angles as shown in the photo and stuck each in place with a smear of silicon between the tabs and the body of the light where there were already small holes designed for the original divider. The mass of the dividers requires little sticking and will not affect handling!
The extent of the illuminated parts of the LEDs I have used can be seen in the photos. It is this generous emission of light which, unless shielded, lights up the indicator lens when the stop/tail lights are on, and vice versa.
Regards
Bill
Attachments
divider-in-place.jpg and
tail-light.jpg and
dividers.jpg and
bill griffiths
Second Gear
Second Gear
 
Posts: 171
Joined: 22 May 2007

PostPost by: elanfan1 » Wed May 24, 2017 8:12 am

Seems like a reasonable solution though I'd have thought a plain piece of aluminium would reflect more light out than black which would absorb it.

Don't mean to come over as a prat here (yeah, yeah nothing unusual there I know!) but a lot more light is transmitted through both the red and amber parts of the lenses (which filter out all but the red/amber element of white light) if you use a red and amber coloured led which is purely that wavelength/colour so most of that light passes through.

I was looking into this several years ago when these lamps were first coming onto the market. Technology has leapt on since then! One of the things that doesn't seem to get mentioned is that the operation time on a red led stop lamp is a lot quicker than a filament bulb and could buy you a few metres more of stopping time from an encroaching SUV which could stop an accident altogether. They also need a lot less power so I'm guessing if you get earthing issues they are possibly much more likely to continue working??

I'm going to start a specific LED lighting thread so maybe everyone can add their own experiences
Steve

Silence is Golden; Duct Tape is Silver
User avatar
elanfan1
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2238
Joined: 13 Jan 2004

PostPost by: bill griffiths » Thu May 25, 2017 4:20 am

My two 1973 Astons came with a blue plastic Lucas box in the boot for the purpose of dimming the rear lights at night time.
Seems such gentlemanly behaviour is now out of date, but as with intermittent wipers discovered accidentally by Lucas, the rear lights have first to come on!!
Anyway, I can assure you that no enhancement by reflection or colour coordination or otherwise is required in the LED equipped tail lights!
As to a red stop lamp operating more quickly than a fillament bulb, perhaps you are confused with CFL delay.
LEDs and incandescent bulbs are both instantaneous!
Regards,Bill
bill griffiths
Second Gear
Second Gear
 
Posts: 171
Joined: 22 May 2007

PostPost by: JJDraper » Sat May 27, 2017 9:07 pm

As to a red stop lamp operating more quickly than a fillament bulb, perhaps you are confused with CFL delay.
LEDs and incandescent bulbs are both instantaneous!


Sorry Bill, LEDs do come on noticeably quicker than incandescent bulbs - it is only milliseconds, but this does affect reaction times. I don't know many cars that use CFLs for rear lights (possibly the Quasar motorcycle).

Jeremy
User avatar
JJDraper
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1031
Joined: 17 Oct 2004

PostPost by: mbell » Sun May 28, 2017 1:11 am

I switched the front side lights on my daily over to Led bulbs. The car does a bulb test ignition on. It does it by a very quickly pulse and checking the current flow.

With the normal bulbs you can't see this happening as the pulse is narrower than a filament bulbs warm up time. With the led bulbs you get very visible flashes. (Also have to get special led bulbs that don't tiger the bulb warning light)

Whether the few ms difference in a makes any real difference I real life I am not sure
'73 +2 130/5 RHD, now on the road and very slowly rolling though a "restoration"
mbell
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2691
Joined: 07 Jun 2013

PostPost by: The Veg » Sun May 28, 2017 4:50 pm

In my experience with the high-tech motorcycles from BMW in recent years, preventing a light failure warning means adding resistance to the lamp, so that the system thinks it's an incandescent lamp. You can get better lighting with the LED, but you lose any benefit of lower current consumption if you have to fake-out the system with higher resistance. Probably no issue for most cars, but something to be aware of.
1970 Elan Plus 2 (not S) 50/2036
2012 BMW R1200GS
"It just wouldn't be a complete day if I didn't forget something!" -Me
User avatar
The Veg
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2329
Joined: 16 Nov 2015

PostPost by: mikealdren » Tue Jun 06, 2017 8:23 am

The Veg wrote:In my experience with the high-tech motorcycles from BMW in recent years, preventing a light failure warning means adding resistance to the lamp, so that the system thinks it's an incandescent lamp. You can get better lighting with the LED, but you lose any benefit of lower current consumption if you have to fake-out the system with higher resistance. Probably no issue for most cars, but something to be aware of.


Bulb failure warning on an Elan +2?????
mikealdren
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1224
Joined: 26 Aug 2006

PostPost by: The Veg » Tue Jun 06, 2017 4:54 pm

Of course not, but something to be aware of in case anybody reading is contemplating their use in more modern applications.
1970 Elan Plus 2 (not S) 50/2036
2012 BMW R1200GS
"It just wouldn't be a complete day if I didn't forget something!" -Me
User avatar
The Veg
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2329
Joined: 16 Nov 2015

PostPost by: mbell » Tue Jun 06, 2017 5:52 pm

The daily is BMW e39 so these were model specific bulbs. They have quite a large aluminum heatsink so wouldn't be surprised about them having large resistor in them.

I fitted them for vanity reason (white v yellow-ish side lights) so not exactly worried about power consumption. I think the 150A water cooled alternator should be able to cope....
'73 +2 130/5 RHD, now on the road and very slowly rolling though a "restoration"
mbell
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 2691
Joined: 07 Jun 2013

Total Online:

Users browsing this forum: No registered users and 11 guests