Good comments!

Those "xenon" lights are really not what they are cracked up to be. The fake "xenons" may have a slight bit of xenon in the capsule but they don't have the ability to emit light anywhere near true xenon bulbs. Their light comes from a filament and not electrically-charged gas. Their improved whiteness is primarily due to the blue coating on the bulb. It acts as a filter to change the visible color of the light coming out of the other side. Many manufacturers then increase the wattage of the bulbs somewhat to compensate for the coating. This, of course, generates more heat. If your bulbs are in a housing that is only marginally adequate for the amount of heat generated you could easily get into trouble with the faux xenons. This is true with the dash lights as well as other applications. This is one reason why I've been considering the white LED's. If someone would make an LED assembly to fit the dash with the correct base on it I think it would be a nice alternative.

Can you post an example of what you are talking about? ie.. these LED lights?

THanks

Here's a website that does some LED automotive bulbs.

http://www.jamstrait.com/

You may have seen some of the LED flashlights that are on the market now. They even make small LED keychain flashlights, sometimes referred to as "squeeze lights" because you squeeze them to illuminate them. For their size they put out a remarkable amount of light. The ones with clear (white) LED's are very white and I believe they would make an ideal replacement for dash lights. One thing I'm not sure of though is whether they can be dimmed with a rheostat. If not it may be all or nothing, so to speak. They would certainly put out less heat than anything else on the market though.

Ironically, I may have just found what I was looking for. According to the Sylvania website, the instrument panel bulbs for my car are 2721. The 2721 bulbs cross-reference to the #74 LED bulb on this website.

http://autolumination.com/194_marker.html

I haven't pulled the original bulbs out to look at them. Does this look like the proper size and the proper base? If so, I may give these a try. If someone can verify that they look correct I'll order a set for my 300SD and report back on how well they do.

Well,

The eurolite bulbs that I used for the dash lights (2) were Eurolite #194. See here:
http://www.toucanindustries.com/index.php?src=products&srctype=display&back=products&id=55597&submenu=Eurolite&category=Replacement% 20Bulbs&pos=15,15,41&pos=15,15,41

My car calls for 2721 bulbs as well, but I used #194 bulbs which look very similar to the 194 bulbs on the page that you provide. I don't know what the #74 bulbs would work with... maybe some of idiot lights in the dash?

BTW... AWESOME INFO

I had the dash out of my 84 before and decided I was going to paint the prisms around the light bulb, upon opening of it I noticed it was just dirty. I took some q-tips and cleaned everything inside there until the q-tip came out clean. I swapped these bulbs with the blinker lights or some less used ones (didn't have any new ones on hand). I still have a little problem seeing it when I'm in a city with the bright lights outside shining down on me, but when out on open roads in the country I dim it just a little bit. I'm pretty happy, it cost me nothing, no risk of melting anything and a VAST improvement over what it was. :)

Eurolite #194 LED bulbs
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33713&item=2426163076

Eurolite #194 XENON bulbs
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=36476&item=2425840562

I needed to revive this older thread to solve an issue I have had.

For one, where is my pentometer for the dash and cluster? I cannot find one. :confused:

I purchased the car from the shop that I detailed and did odd work for. When they got the car I also replaced the Evap (before purchase, I actually got paid to repair my car!). I pulled the dash apart, if anyone has done this, you would think that I would notice a pentometer.

Anyway, I was not able to complete the evap replacement, the tech finished up the job. Ok, he did a pretty good job, but not perfect. At one point the cluster lights as well as the dash lights died on me. I thought, for some odd reason, to push on the cluster. The lights came back.

Recently the dash and window switch lights are out, but the cluster lights work. I tried again to push the cluster, with no positive results.

I don't really want to have to pull the cluster out if there is something else I can check.

Any ideas on why I don't have a pentometer, or why my dash and consol lights are gone?

There are lots of reasons your dash lights may have gone out. My bet is that the multi-pin connector at the back of the instrument cluster is loose or coming apart. I'm afraid you'll need to remove the cluster again to check it. There are several ways to remove it. My favorite is a bit more work but the safest. Remove the driver's side kick panel below the dash and reach up behind the dash and push the cluster out part way. The multi-pin connector is on the left side behind the oil/fuel/temp gauges. Make sure it's tight and not coming apart. You may want to wait on that though if you want to get at the potentiometer. It's easy to find but you'll need to remove the whole cluster to get at it. To remove the cluster pull out the right side and reach behind to carefully unscrew the speedo cable. Then push in the right side of the cluster, pull out the left side and wiggle off the multi-pin connector and with a small wrench disconnect the plastic tube that connects to the oil pressure gauge. Reassembly is in the reverse (be sure to reconnect the oil pressure line or you'll have oil on your pants when you start up the engine. Do not overtighten either). The potentiometer is the small, square white bakelite box (about 1" x 1")right behind the odometer reset button. You'll need to remove two screws and wiggle it a bit to get it off.

I think that's all you need. This is a pretty easy job and the rest you can probably get from earlier comments in this post or in a search. Have fun.

So can remove the cluster without getting underneath the car? I just need to not pull the cluster out all the way before I loosen the spedocable?

Did all the clusters have the square, white, backlite box? I don't see it. **** I don't really care, I usually turn them all the way down in my BMW anyway.

I will do the kick panel thing though. I have smallish arms, so I think I will just reach up there and do it.

http://web.archive.org/web/20040602194423/http://instrument.articles.mbz.org/renew/

http://web.archive.org/web/20040603004113/instrument.articles.mbz.org/dimmer/

Dimmer fix
 

Greetings,

Just beginning to get into the 123.

One of first challenges was no instrument panel illumination.

Took off the instrument panel - unscrew the driver under dash panel, then reached up and pushed out the instrument panel - too cool that it pushes right out ...

Disconnected the wires, vacuum line, tach, etc ...

Ended up replacing the bulbs with ones I got at my local German car repair guru, no joy ( after reinstalling dash, of course ) - back to having the instrument panel taken apart

Took apart the potentiometer ( it unscrews from the back of the instrument panel )

(( The potentiometer is the dimmer knob ( left bottom on the front of the instrument panel ) ))

Anyways, some corrosion had built up inside the potientometer ( like the white powder corrosion you see on batteries ), I blew it out ( cool that it was built that way ) and doused it in parts cleaner ( yes, probably a little overkill )

Screwed it back on the back of the instrument panel , reconnected all connections to the back of the instrument panel ( lamp with wire with #1 tag is glow plug ) and ....

Got dim lighting for instrument panel, but much much better than holding a light so I could see speedometer when I drove it home for the first time...

Low tech newbie contribution ....


Enjoy,

Ive got some int lights working, others dont. 1 of the bulbs in cluster work, other out. No shifter light, some aCC lights work, others dont. ALL the bulbs are good. What the hell is this? Sometimes all lights go out, I smack the dash and the half that work come back on.

300D turbo 1987.

bulb specifications 300D instrument panel
 

I want to know if I can just replace the existing dim bulbs in my instrument panel with LED lights that will fit in the existing sockets. I haven't taken the panel out yet, I'd like to go buy the LEDs before I do that. What kind of socket is it?

Has anyone bought LED lights from any of the several suppliers online (http://www.ledtronics.com/Default.aspx, http://www.ledlight.com/) etc? If so which of the confusing array of LEDs should I buy to fit directly into the existing sockets in my instrument panel.

Many thanks.