free hit
counters
Dash illumination - Interior/Exterior/Lights/Glass/Alarms/ICE/HVAC - The Lotus Forums Jump to content

Recommended Posts

Hi all,

While my wife is away sunning herself in Tunisia I get to stay at home and look after the kids (and more fun - the Car)

As part of the yard long list I started the week with (rear springs and shocks and a new fan blade already done :) ) I vowed to try and improve the woeful dash illumination. Armed with previous posts on here I ordered some LED replacements for the '194' push in type 5w bulbs that are used in the ancilliary gauges and some push in bulb holders to allow fabrication of something for speedo, tacho and boost which have a screw in bulb (reminded me of a torch bulb).

I have just finished the job. Have to wait til tonight to see if it has helped. I went for green LEDs for a 'night vision' look just in case they were too bright although initial observations are that the dimmer still works.

I did find a useful 'bodge' (an engineering solution that CABC would have been proud of) to get the bulbs into the speedo etc.

By cutting the existing holder about 3 mm up the conical section and opening up the hole in the centre (the metal is very thin and folded back easily). I was then able to trim the plasic on the bulb holder (cheap on e-bay got 10 for a fiver pre wired) so that it fitted into the original.

Bending the tabs on the push in holder slightly to avoid a short circuit and a little superglue to hold the two bits together (although it was a press in fit I didn't want it to fall out) and the you can just pop the new LED bulb in.

Then just splice into the original wiring connections and viola!

With the LED's if they don't work turn them through 180 degrees usually fixes it. The LED bulbs I used had 4 individual LEDs per bulb.

Like a prat I took no pictures but I'll do a drawing and scan it in if anyone is interested.

Share this post


Link to post
Share on other sites
Upgrade today to remove Google ads and support TLF.

Brian

Got the bulbs and the holders on E bay (from hong kong)

Share this post


Link to post
Share on other sites

I recently tried this with mine and it didn't look very good at all. I got the widest angle led's i could find but parts of the gauges looked too bright and other areas were very dim. I've just put some new bulbs in now.

Share this post


Link to post
Share on other sites

Dave,

Don't know what the dash lights are like on the later cars but on the S3 it was dreadful by modern standards. I may have made it worse but then I can always revert to standard bulbs. An added bonus is that I won't have to find the screw in 'torch bulbs' now that I have press in holders and I can go for 194's throughout.

I have seen white LEDs and some monsters that had 7 or 9 individual LED on each bulb so if this doesn't improve then I can always try those (although I couldn't find them in green or red so didn't go for them in the first place)

Will be picking my eldest up from cadets this evening so will post up the results. (gives me an excuse to take the wife's car :) )

John

1000869q.th.jpg

1000868f.th.jpg

taken without flash (car was running so not sharp and a bit blurred but might give a feeling for brightness).

I like the green tint but will wait to see what the car's owner thinks when she gets back from her hols.

Speedo is a bit uneven and brighter at the 70 mph section but it feels like an improvement. If anyone is contemplating this mod and wants to pop by one night and have a look you are welcome - just PM me.

John

Edited by Mr_John111

Share this post


Link to post
Share on other sites

Bit of a post script for this thread.....

As one of the bulbs had blown I took the bulb holders out to reattach them with Araldite (the super glue wasn't man enough for the job)

So I took some picture of the modification I made to the original screw in type bulb holder below

picture021.th.jpg

picture020vh.th.jpg

picture019x.th.jpg

Links to higher resolution pictures in Imageshack

<a href="http://img576.images...picture021.jpg/" target="_blank">

<a href="http://img11.imagesh...cture020vh.jpg/" target="_blank">

<a href="http://img576.images...icture019x.jpg/" target="_blank"><

John

Share this post


Link to post
Share on other sites

The common issue with LEDs is they are only very bright over a small angle.

I make my own LED bulbs and what I tend to do is use 5-8 LEDs and fan them out so they cover a wider area.

The ones I am making for the GT2 dash are 6 LED - 5 shine outward and the centre one shines directly outward - try also to paint/coat any backings in white as this will help the light bounce around.

Share this post


Link to post
Share on other sites

thumbsup.gif

blueendof020.jpg

I sourced all my bits from Ultraleds. http://www.ultraleds.co.uk/ and they are having a May Bank holiday sale. 15% off purchases of over £30. Use 42336 in the voucher coupon box at checkout.

Share this post


Link to post
Share on other sites

I got all mine from ultraleds until I took a few apart and noticed the 'ultrabrite' ones were actually the standard ones with a smaller value resistor in !!! :lol:

I also had a few blow out on me, took them aparat and also noticed the wrong resistors were in place, the things were drawing 2-3 times the max forward current and lasting at all.

If you an solder the best bet is to buy them on eBay and make your own, here's one I made earlier :

4566350654_0f4afb7ecf.jpg

All I did was take the old blown bulb and crunch the ends off to make the fitting, bit of vero board, 8 LEDs (2 parallel rows of 4 in series) and 2x 100 gnome resistors to limit the current. Whole deal works out to about £1 a go.

The bulbs on eBay are also a lot cheaper than ultraleds, just trying to save ppl a few pennies.

Share this post


Link to post
Share on other sites

Jonathan, can you show us the back of that LED array please. Also, what spec of LEDs are you using with those resistors?

Share this post


Link to post
Share on other sites

When fitting the LEDs for my speedo and tacho back-lighting I used these :-

Lumileds%20Luxeon%201%203%205.png

They are Luxeon 1W batwing emitters which spread the light out sideways (hence the odd shape) instead of out the front with normal LEDs. They are available in a wide range of colours, but you need do a bit of assembly and add a current limiting resistor to the bulb holder.

For the other gauges I found that the narrower angle Luxeon LEDs gave a better result.

Hilly

Edited by hilly

Share this post


Link to post
Share on other sites

Its a bit of a poo photo (blame the iPhone, I do...) but :

4565918471_73d3ff590c.jpg

You get the idea. The LEDs are equivalant 25watt (they are 3mm LEDS, VERY bright), I bout 100 from china for 4p or something silly, becuase I'm super nice I'll give the formula as well.

The Formula: R = (Vs - Vf) / If

Where:

R is the resistor value

Vs is the supply voltage (in this case about 13.8V from the alternator)

Vf is the forward voltage drop across the LED (refer to LED data sheet or meter it with a diode checker

If is the forward current through the LED (refer to LED data sheet but usually 20mA is ample

In my case they are 3v forward bias voltage, I have 4 in series so 4x 3 = 12V,

take that from 13.8v = 1.8V / say 0.02Amps = 90gnomes = prefered value of 100

Drip solder into the bullet ends and then push the board in - job done.

I always try to use white light with red filters on dashboards - white gives the best light ouput power and red is less taxing on the eyes (green being the most) which is why 90% of dash illumination is in red or orange.

Share this post


Link to post
Share on other sites

Stig,

They look a bit long to me

Perhaps buy one and compare it to the standard '194' bulbs in the ancilliary gauges?

For my refurb I used volts oil speedo boost tach water and fuel so thats 7 all together.

The most important part is 3 x bulb holders as whilst the ancilliary gauges are a straight swap the speedo tacho and boost are not.

Good luck

John

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×