No dashboard light-- 1983 300D Mercedes

Hi,
I have had my 1983 300D for about 6 mo, and the entire time the light on the dashboard has not worked. It flickered on ONCE when I was on a roadtrip, but I don't know why, and it was momentary. Leads me to
believe something is loose? All fuses look intact. All other lights in the dashboard work, i.e. the glowplug light, oil, battery, etc when you turn the key.
Dead bulb? Wiring? Any ideas? I don't think I have the dimmer switch that I saw mentioned in some previous postings as a troubleshoot....
Does anyone know how to replace the bulb on the dash ?
Hoping not to get a speeding ticket tonite- Kate
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@gmail.com wrote:

Have you twiddled the dimmer? (same button that resets trip meter)
Regards, WS
--
change to leews to mail

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
ws wrote:

Most likely that's what it is. Sometimes just working it back and forth many times will help. Or you may find one spot, where if left alone, it will work at that setting. To fix it right, you need to pull out the instrument cluster, which isn't that hard to do. Then you can remove the rheostat from the cluster. I sprayed my 26 year old one with electrical contact cleaner and then worked it back/forth many times. And voilla! good as new. You can also buy a new one, but they are expensive, about $60.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It is almost certainly the dimmer rheostat which controlls all dashboard gauge lights but not the idiot lights.
Scary though it may sound, you can pull the entire instrument cluster out very easily with two bent pieces of coathangers. Then you unscre the rheostat and replace it. Although, they can be repaired, I Was able to fix mine.
A short term solution is to wiggle the knob back and forth until it works and as soon as it does let go and leave it there. This *usually* works.
Repair instructions can be fond here:
    http://articles.mbz.org/instrument /
--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
There are TWO small buttons below the instruments. One zeros the trip odometer with a push, the other rotates to dim the lights.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I tried toggling the dimmer button but nothing happened. So there are two buttons, the one of the left resets the counter and also spins, and the one on the right sets the clock. Which one is the dimmer? I tried moving both around, but to no avail.
Any other ideas? Do I need to push the buttons in when I wiggle/spin them? Is it time to open up the dashboard?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
No other ideas, your '83 must differ from the '79 I once owned.
The rheostat tend to be flaky as they age.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Yup, time to open it up. I t is absolutely the one that resets the odometer.
Pulling the dash is only hard/scary if you haven't done it. It's stupid easy coming out and going back in once you've done it though. DO disconnect the battery first!
Your options are: 1) get a new rheostat - not cheap but you'll have 100% complete dimmable lights. 2) repair yours - sometimes the wire just comes off and it can be repaired. 3) just solder a junmper wire from one side of the thing to the other. Your dash lights will be full on all the time but if you can live with that it's a cheap fix.
--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Hello. Its the dimmer switch control. Its very common on these models. Moisture gets in and stops contact. You need to flip out the instruments/clocks cluster and clean the dimmer switch. reply for more info. daniel

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.