No dashlight at all

[pablo_o2]

on my dashboard nothing is illuminated, not the clock not the instruments, not the heaterlevers, not the fan turnknob not the cigaretlighter. I checked the fuses in the motercompartiment and they are ok. Lightbulbs are ok also. Does anyone have had the same problem yet? Can it be something is not connected or cut?

[Douglas]

Have you tried to adjust the knob that controls the brightness in the center gauge? It can be tricky because that knob turns into an all-or-nothing adjustment over time. Also, you generally need to be moving to adjust it.

Douglas Kim
New York, NY
280 SL #016220

[Mike]

I agree with Doug and offer the following addiional point as this same thing happened to me recently.  Upon inspecting the fuses, all appeared normal.  The fuse that handles the dash lights is on the end and I noted that when I removed the fuse box cover, the dash lights came on and then when I replaced the fuse box cover, they went off.  I fond that you have to be careful when attaching the fuse box cover as you can tighten it in a way that causes the fuse on the end to become loosened enough that it does not make contact.

Michael L. Hund

[mdsalemi]

Some information for those that don't know.  The brightness control is a genuine, old fashioned wire-wound rheostat that does not last 35 years, generally.  Even if you send the instruments out for repair what they generally do is remove and bypass this control so you are on full-bright all the time.  Those that pay attention to such things will notice that "full bright" on our 113's is somewhat less then 1/2 bright on a modern vehicle!  I had Palo Alto speedometer find or put together a working rheostat for me only to find that I have left it on full and wish I had things even brighter.  But then again I rarely drive the 113 at night so in reality I'm not too concerned about it.


Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored

[Raymond]

35 and 40 year old rheostats are just going to wear out and corrode.  If you roll it back and forth a little, you may get lucky and find a point that makes contact.  Like the man said, it's usually all or nothing because the lowest possible resistance is most likely to pass the voltage.  If the dimmer is dead, you could jumper across it and have the lights on full all the time, or you have to replace it.  Any 12 volt rheostat would work electrically, but mounting and space requirements probably dictate that you get one designed to fit behind the instrument.  

Anyone know if a properly fitting one is still available?

Ray
'68 280SL 4-spd Coupe

[pablo_o2]

thank you all, i also tried to turn the reostat allready. I think I will just bypass it as i understand that full brightnes isn't so bright at all.

Paul Haems
'68 white 280 SL

[Douglas]

Try it while you're driving at night. It probably won't work if you're idling.

Douglas Kim
New York, NY
280 SL #016220

[Jonny B]

Did you try the search function using "dash" or "dashboard"? There have been a number of posts concerning the dash lights. The grounding set up is another thing to check. This is the brown wire that should be connected to the back of each of the main instruments at the center post, that holds the keeper in place. Also make sure you have the correct keepers for the tach and speedo, they are not interchangeable. The tach should have a small bump out to allow it to fit over one of the bulb holders. If you can get a copy of the electrical diagram it can be a help.

I think one of the posts also mentioned a way to jump across the rheostat.

Jonny B
1967 250SL Auto

[hauser]

Mine is there but not funtional so it was bypassed and I wish it were brighter than what it is.

1969 280sl 5 spd        1999 ML320          Gainesville,Fl.

[Naj ✝︎]

Original bulbs are 2 watt.
I changed over to 4 watt in the same BA 9 fitting.
That makes it twice as bright?

naj

65 230SL
68 280SL

[A Dalton]

Originally posted by naj

Original bulbs are 2 watt.
I changed over to 4 watt in the same BA 9 fitting.
That makes it twice as bright?


 Yes .  It is hard to even find the 2 watt in the BA9 base now..[Narva-17053, 12v/2w ]..

 The cross for those in 4w. are  Philips -12929, Narva -17131, and Osram -3893.
 Those are all ECE code/..12v/4w

[Naj ✝︎]

Oh, btw,
The 4 watts bulbs are the same as the side/parking light bulbs.
I upgraded those to 6 watt halogen. What white, bright lights now  

naj

65 230SL
68 280SL

[Ed Cave]

Am I understanding correctly that it is possible to increase the wattage of the dash lamp(s) to 4 watts and this will increase the brightness accordingly? Very dim guage lights have always been an issue with my (6v - duh) 356.

Ed Cave
Atlanta, GA

1964 356C
1971 280SL

[Naj ✝︎]

Yes, Ed,
I've done this on my 230sl with good a result.

I've not done the instruments on the 280sl yet but I'm sure the bulbs that light up the air/heater controls are smaller (BA 7s I think) and may not be available in 4 watt. Not tried that - just put the old ones back.

naj

65 230SL
68 280SL

[rwmastel]

Is there any danger in moving up from 2w to 4w bulbs?  They may be (nearly) twice as bright, but they would product more heat as well.  I've never removed any instruments other than the clock, so I don't know if there might be a heat issue.

Rodd
Powell, Ohio, USA
1966 230SL, Euro, Auto, Leather, both  tops
1994 E420

[A Dalton]

I doubt a heat issue would come from a 12v/4watt lamp . Lamp current draw of 12v/4w. is approx. 325 milliamps, so heat energy is low...

[J. Huber]

Pablo and others,

One thing about checking fuses. Although they look fine, it is a good idea to spin them once in a while to keep the contacts clean.

James
63 230SL

[pagodapete]

Does anyone know of a supplier of these 4w bulbs with the BA9 fitting?

Brian Peters
Motoring Investments

[hands_aus]

Pablo,
Is there a light in the cigarette lighter?
Or are you saying that the cigarette lighter itself doesn't work? If the lighter itself doesn't work then there is a separate problem.
Doesn't the cigarette lighter work independently of the dash light rheostat?

Does the fan switch light only work when the dash lights are 'on' OR only when the fan is 'on' AND the dash lights are 'on'?

Bob (Brisbane,Australia)
RHD,1967 early 250 SL, auto

[pablo_o2]

Bob, as I took out the fan switch i noticed there's no bulb inside, neather is there a socket, only an open space. Are there perhaps 2 different versions, one with and one without light? Further the cigaretlighter works well. I think the problem is the rheostat.

Paul Haems
'68 white 280 SL

[Naj ✝︎]

Early fan switches with a plain black knob and a little hole in the middle of it did have a very thin bulb which lit up the hole with the side lights.
Later knobs with the blue arrow do not have this light in my experience.

Not seen any lighting on the cigar lighter tho'

naj

65 230SL
68 280SL

[hands_aus]

Pablo and Naj,
The fan switch on my 250 has the light bulb and fitting. Obviously it was something not included as the models changed.
I had to clean the hole very carefully because it was filled with years of grime.
As I remember, the light bulb is a low wattage one. It mounts low on the body of the unit and has a clear plastic section that guides the light up to the knob... bit like fibre optics.
The clear plastic part goes to the hole in the knob.
I don't have a pic of the arrangement other wise I would post one here.

Bob (Brisbane,Australia)
RHD,1967 early 250 SL, auto

[Naj ✝︎]

Hi, Bob,
On my 230, if I remember rightly, the miniscule bulb slides into the hollow of the switch operating shaft??

naj

65 230SL
68 280SL

[A Dalton]

Bisbane Bob

 Does you 043 knob have a flat on the circumference ?

 Also, how far does the plastic for the optics stick in the knob hole??
Tnx

[J. Huber]

Hmmm. Having never noticed a fan switch light in my 230SL, I just looked. I have the flattened area on the knob and a little empty hole in the center. Is this where a bulb would go? I don't see any metal where a bulb would attach -- just black.

James
63 230SL