The light bulb holder for VDO tacho fell apart today, I went down to Jay car and bought some white LEDs and fitted one up as a trial, it worked great, really bright with a blue tinge, I'm going to do the rest soon.
I searched and I couldn't find a previous post on this subject.
Steve
64vwmark ·
Can you please put up some pics of this? (If you have any)
I would like to put LED's in my stock speedo.
Transparu ·
I did this a couple of years ago for my instrument panel. I used blue LEDs in most part. There ARE a couple of issues.
It isn't just a matter of adding an LED (unless it is a 12V LED). A resistor in series is needed.
One (possibly the only) advantage of an incandescent bulb is that its output is more or less uniformly in all directions so it lights the dials more or less uniformly. Few LEDs are like this. they are much more directional and so some fiddling is required to distribute light evenly. I found it difficult to get things right.
Another issue is that you will be (almost) unable to dim the instrument display as LED's are not responsive to voltage across them as are incandescents. This means that you could find yourself with a display much brighter on a long run than you might find comfortable. I can speak from experience on each of these issues.
It IS pleasing to have the LEDs there though when all is worked out.
Dave
white LEDs and fitted one up as a trial, it worked great, really bright with a blue tinge, I'm going to do the rest soon.
I used 5mm ones like the ones above, it looks great in the tacho, I will see how the others look soon. All I did to fit them was run a drill through the VDO bulb holder, then I siliconed the LED in place, ran a power & earth wire.
Steve
MikeM ·
Dimming instument lights are an ADR requirement and can be classed as a defect on a road side inspection.
Just thought I'd mention that.
1303Steve ·
Hi
Just went outside and checked, my sole LED in the Tacho dims fine.
I don't know if its because I'm old or strange or both, but I cant see the need for dimming dash lights, I always have mine on full bright in every car I drive.
Steve
56astro ·
Steve, drive long distances with them on full brightness, then dim them for a while.
I find that if they are bright, I get bad eye strain. I have mine dulled to the max.
Driving around town you probably won't notice the difference.
1303Steve ·
Hi
It must be my age or too many drugs in my youth, I do drive long distances, if I dim them I cant read them.
Steve
56astro ·
Haha - a combination of both.
I guess it's a matter of finding a setting that allows them to be seen, but doesn't cause eye strain.
1303Steve ·
Hi
I took this picture so you can see what my tacho looks like with LED fitted, you can see how yellow looking the lighting is in the other gauges. The light is very strong directly behind the LED but is very acceptable around the rest of the gauge as Transparu indicated would happen. I saw some LEDs on Ebay with little reflector caps on them, this would stop this problem.
Steve
sinecure ·
High Intensity LED's will accept voltage from 1.5 to 4.4V, with a corresponding brightness change.
Resisted through for 12V, dimmers will still work quite effectively, if the pot controller is applicable for this 3 odd volt change.