Easy dash cluster light fix for W123's - PeachParts Mercedes-Benz Forum

lietuviai · #1 12-05-2004, 07:08 PM

I figured there are probably other members out there that may be experiencing the same problem I did. On W123 models (other models are probably similar) the two upper dash bulbs installed using plastic bulb sockets with brass pins that connect to the circuit board on the back side. As these sockets become older or the bulbs have been changed over time, the brass pins can end up being bent the wrong way and the bulb no longer has good contact (as I did). Simply bend the pins in toward the socket then they will make better contact and the lights should work.
There may be other problems plaguing your dash lights as well, such as a corroded rheostat but that's something I'm not going to get into.

kamil · #2 12-05-2004, 09:11 PM

good advice. i'll me taking my cluster out soon so I can change the clock and I'll take a look at those while i'm there.

thanks

Richard Eldridge · #3 12-05-2004, 09:22 PM

You are right that cleaning the sockets and bending the contacts as well as cleaning and painting the prisms will improve the lighting. I did this, but there is still not enough light to see the gauges or read the odometer easily.

This company has 12 v LED's, which normally are much cooler than the standard incandescent bulbs, and there sems to be quite a variety of different sockets, if you scroll down the page.

http://www.superbrightleds.com/cgi-bin/store/commerce.cgi?product=CAR

Hope this helps.

kamil · #4 12-05-2004, 09:27 PM

I might buy these bulbs... I hope they don't melt the sockets

dmorrison · #5 12-05-2004, 11:00 PM

I did rebuild the instrument cluster in my 300TD. I painted the interior of the bulb housing white. A gloss white so it reflects as much light as it can. I also installed 5 watt bulbs verses the 3 watt bulbs. The instrument cluster is now quite easy to read and is illuminated quite well.

Make sure the prisma are clean, don't paint them just clean them. They are the items that transmit the light to the instrument panel.

Again paint the bulb interior white and clean the prism. I got the 5 watt bulbs from EAS, you have to call them to get them.

http://www.***********************/

Check to see if Phil at Fastlane can get them.

Bend the contacts and clean them with steel wool or an abrasive cloth. that way the oxidation on the contacts will be removed.

Dave

pmari · #6 12-06-2004, 12:30 AM

Quote:

A gloss white so it reflects as much light as it can.

Flat white will actually reflect more lumens. http://ciee.ucop.edu/Siminovitch1998/
But that's splitting hairs

dmorrison · #7 12-06-2004, 01:36 AM

Quote:

Originally Posted by pmari

Flat white will actually reflect more lumens. http://ciee.ucop.edu/Siminovitch1998/
But that's splitting hairs

Actually

"The fixture efficiencies of the white paint fixtures do not appreciably vary from the use of flat, semi-gloss, or gloss type paint. Some differences in efficiency can be seen among the Alanod fixtures"

Now yes the chart does show a differnce of 210 Lumens betwen the flat and gloss. But the majority of Testor paint comes in gloss. So instead of searching for an enamal that is flat I chose the testor paint.

Dave

kmaysob · #8 12-06-2004, 02:23 AM

use an eraser on the contacts if u can

W123dMercMania · #9 12-06-2004, 05:57 PM

Richard Eldridge]

http://www.superbrightleds.com/cgi-bin/store/commerce.cgi?product=CAR

Its confusing. Could you please kindly recommend which of the LEDs will fit 123 dash to illuminate the gauges and the odo digits. Thanks

Richard Eldridge · #10 12-06-2004, 10:54 PM

I am sorry, I have not tried LED's and I do not know which would fit. I think there are five or six bulbs in the instrument cluster and you would need to take one out and examine it, then examine the LED's to see which would fit best. It might be you would have to get a set of sockets and fit them into the cluster, if these LED's were not easily fitted to the sockets on the instrument cluster.

Once you get inside the cluster, it is easy to see which bulbs light which instruments.

LED's do not produce much heat. Others have written in this forum that anything brighter than 3W will eventually melt the prisms. I do not know that this is true, but is seems possible.

These LED bulbs are not so expensive that you could not buy a dozen or so and figure out how to adapt them to your instrument cluster.

Once one of us gets around to doing this, then they can report back to the Forum and it will be much easier for the rest of us, and we shall all hopefully be able to drive our aging and improved vehicles without squinting at our speedos.

I am sorry if this was confusing. Some study and LED's and several hour's' work and we can have a solution.

PS when reinstalling the cluster DO NOT forget to reconnect the oil pressure gauge tightly, or it will leak on your carpet and the neighborhood children might learn several new words unfit for mixed company.

To check how much heat a given LED produces, it would be useful to hook it up to as 12v transformer for 15 minutes or so and feel it (cautiously at first).

redbaronph123 · #11 12-06-2004, 11:59 PM

i'll be going the LED route on my cluster by this weekend.. i'll try to take a picture of my work as it goes along.. and hopefully i do get to finish the work. eheheh..

Carrameow · #12 12-07-2004, 08:58 AM

Didn't tighten it enuff, went in to work with oil on my shoes and egg on my face, found out that you can use Lanolin Hand cleaner to get oil stains off of suede, and felt very foolish because just the night before I posted about why my oil pressure was slightly less than normal...