LED Bulbs - mss1tw
Has anyone replaced any bulbs in their car with the new LED sort? I want to give it a go but I want to find some that have the resistors built in, I have looked but all the different websites lead to information overload after a while.

LED Bulbs - Altea Ego
If your car has CAN bus wiring they need the resistors. However on some CAN bus applications they wont work. If its an older car with real volts and sparks then it will


Car light optics (the relectors and lenses) are not designed for LEDs are the output therefore is rubbish.
TourVanMan TM < Ex RF >
LED Bulbs - bell boy
if i was a bit younger i would get a light for my car from the scrappies go down maplins and buy a big bag of leds and make my own up.......
but i couldnt be bothered anymore :(
LED Bulbs - DP
I use them as backlights in the instrument panel of the bike. After two bulbs popping in quick succession, and with the unbelievable hassle getting the clocks out of a faired motorcycle, I thought it was worth the expense to make sure I never had to do it again.

They work well.
LED Bulbs - tr7v8
Yup failed the MOT on the 944 because I had no sidelights with ignition off as my car has dim dip. Fitted LEDs into the fog/driving lights as sidelights which are a massive pain to change, MOT Tester now happy. Oh & they're white not chavvy blue!
LED Bulbs - Adam {P}
I may make myself look even more stupid than I already appear but I've never seen these before. Are we talking bulbs that have little LEDS in them? If so, how come I haven't already bought them?!
LED Bulbs - Red Baron
They are not exactly bulbs. They are little diodes (semiconductor junction) that have an encapsulant around them. The combination of the diode emission and the colour of the encapsulant will give the desired colour output. As already mentioned above, the light output is minimal which is why you need lots of them just to equal one filament bulb. For this reason their use is limited to tail lights and indicators.

Would be an expensive conversion for any car.
LED Bulbs - mss1tw
For this reason their
use is limited to tail lights and indicators.

I probably should have said, this is all I want to do!
LED Bulbs - bell boy
New type mot (siemens) the sidelights not working with keys out of ignition is NOT an mot failure.
LED Bulbs - Imagos
Don't need to fit 'em. my Passats already got 'em!
LED Bulbs - martint123
Red LED replacement brake/tail lamps sometimes don't work behind red lenses. The LED's are very narrow wavelength of light and sometimes will not appear through the red lens.
LED Bulbs - Hamsafar
I bought a load from America for about £35 a few years ago, not only did I have to pay £24 duty and Parcel Force admin fee, but they were absolute rubbish. These had normal bases, and a disc covered in 5mm LEDs these lit up a small area of the lense and looked stupid and while bright from the right angle while looking directly at the source, it was obvious they didn't actuall disperse much light overall, so I ditched them. The trouble is the LED light doesn't shine on the reflector, yet the lamps are designed for this to happen.

I think if you wanted an LED project, you'd have to get another set of lamps, and cut them open with a dremel or red-hot knife and install panels of LEDs mounted in veroboard.
This is pretty much what the newer ones and newer low-profile emergency vehicle light bars use.
LED Bulbs - Pete M
Sorry to hear about your experience, Ashok. In the last few years great advances have been made in the light output of LEDs. Early ones could only produce a few mcd (milli-candelas) but now outputs of 30,000 mcd are common. There are a number of different wavelengths available and red, green, orange, yellow, blue, white, purple, Infra-Red and Ultra-Violet colours.
You can buy single LEDs rated at 5 Watts, which with a simple lens, are effective as a cycle headlight. The issue of directionality can be addressed by providing diffusing optics. A number of after-market car lamp-to-LED conversions are being produced in Asia, and more and more cars and motorcycles are now coming as standard with LED tail lights.
LED Bulbs - Hamsafar
Yes, I know about these new LEDs used by OEMs and they're definately going to replace filaments, but have never seen them for sale seperately to the 'end user'.


was what I had and from the same place!

I once made some LED light panels for a strobe system using veroboard and hyperbright LEDs, and made a white one with 98 LEDs for an outside porch light at home.
LED Bulbs - AR-CoolC

There are mixed veiws on these, on other forums I frequent. Some love 'em, some hate 'em. But personally have never tried them out.
LED Bulbs - Altea Ego
The problem is the light assembly optics. The optics are the light assemby reflector and lenses. They are computer designed with the bulb filament in a known postion, shape and output profile.

Leds dont match this profile. Hence the optical properties of the whole lamp assembly are screwed. Cars designed to use LEDs have totaly different lamp assemblies.
TourVanMan TM < Ex RF >
LED Bulbs - Statistical outlier
It's indeed as complex as TVM describes. I had a company come to me to have their light system modified to run on LEDs instead of a halogen bulb. Now admittedly there were stringent requirements for the light pattern and intensity (Same as cars I'd imagine, it was a transport related application) and they were horrified to find out how serious a job this was to do properly. I think they expected £2-3k! We corrected them, and they went away to have another think...
LED Bulbs - Pete M
Trucks here in New Zealand are now starting to use LED tail/brake and indicator assemblies. These are just a rectangular panel with a large number of LEDs in a matrix. As there is no 'styling' requirement, they are probably quite simple. There are no optics as such, the LEDs just shine out of (I think) a clear moulded block. The advantage for the operator is that the reliability of the LEDs means that they are 'fit and forget'. They seem to be just as visible as a normal bulb arrangement, if not better, in that the light comes from many points, not just one. tinyurl.com/elbkh shows one type.
LED Bulbs - Red Baron
Fit and Forget...not too sure about that. Yes, to a point in that and LED light system consists of a matrix of individual LEDs such that when one of them goes then there are still 23 other ones that do work. Lets just hope that the LEDs are wired up in parallel and not in series otherwise the remaining ones will fail even more quickly.

You can envisage that some failing LED light systems won't get replaced until most of the array has fried.
LED Bulbs - SlidingPillar
Quite a lot of the replacement "style" LEDs are not legal in post 72 cars.

I legally use them at the back of my three wheeler (1930), but as the light units are so poorly designed, my LED "bulbs" give better illumination than filament bulbs.

While the possibility is folk might not inspect them properly for continued correct operation they burn a fraction of the current, are much better at withstanding vibration (why I use them) and have a much longer lifetime. Given this, new cars with properly designed LEDs might have a safety advantage.

LEDs don't like heat though so if you have sidelights close to headlight bulbs, I'd not advise even trying them.
LED Bulbs - Number_Cruncher
I had no sidelights with ignition off as my car has dim dip.

That's odd. The Vauxhall implementation of dim dip used to put the sidelights on with the engine not running, and then, via a tee into the signal wire to the oil pressure switch, would sense the engine was running, and feed the headlamps at reduced power.

Is it possible that you had a fault with the dim-dip, or was this as Porsche meant it to be? i.e., are all 944 owners now rigging up alternative sidelamps?

LED Bulbs - ffidrac {P}
I bought a pair of stop/tail LED replacement 'bulbs' a couple of years ago and fitted 1 to the car leaving the other as original. I enlisted the aid of a friend to press the brake and turn the sidelights on so I could determine if they were suitable.

On my Kenari the LED tail light was visible for about the same angle round the side as the standard light and about the same brightness.

The brake light was actually brighter with the LED and the added bonus of no warm-up time operated noticeably faster than the standard lamp so I fitted the other LED and called it a day.

High level brake lamp is still a filament lamp and you can see the difference in ligh up time, it's not much but it's noticeable!

Ask Honest John

Value my car