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Allgonquin
06-29-2014, 08:03 PM
Both my '95 diesel and my 500E have this issue, slightly different for each one. The diesel has the rear tail light portion of the running lights not working on the passenger side. Each tail light has both a side light and a tail light. The 500E has the side light portion of the driver's side not working. The bulbs are confirmed good.

What is really vexing is that I can measure both continuity and voltage for each of the bulb locations. Continuity to the wiring plug terminals, and I can actually measure voltage from the center terminal of each socket to the ground. Now what is odd is that the voltage seems to be slightly less than the ~12V level of the bulbs that do work. But I get no glow whatsoever from the bulb. The center contact is making good contact, and I have buffed all the bulb contacts and the light housing contacts.

And equally vexing is that from time to time the diesel light will just decide to work for a day or three. I have taken the rear light housing(s) apart, carefully prying the ground/socket bar from the plastic, taking it out, and looking for anything odd, and I can find nothing out of order.

It's really driving me nuts that I can measure ~10.5 - 11V on the non-working sockets and I get no light at all. And no short to ground at each socket either.

Anyway, just venting a bit after a non-productive troubleshooting exercise.

Chris

DerFuror
06-29-2014, 11:08 PM
On the 500E, check the tail-light's grounding wire to chassis connection on the driver-side. Disconnect, clean contact surfaces thoroughly & reconnect. Oxidizing connection there can lead to whacky light behavior. I had a somewhat similar situation shortly before my car's first State inspection under my ownership.

I don't know jack about non-.036, but it could be a similar issue with the diesel.

500AMM
06-30-2014, 08:59 AM
Yes, I put my bet on oxided ground points too.
Additionally you should wiggle all fuses in their sockets a couple of times.
Maybe try to switch the bulbs around to see if one is partly failing.

sheward
06-30-2014, 09:13 AM
I had a similar problem with a couple of trailer lights(who hasn't)? The bulbs were ok but would not light until I smoothed the center contact point with a fine file. They looked fine to the naked eye.

drew

Klink
06-30-2014, 05:10 PM
On the 500E, check the tail-light's grounding wire to chassis connection on the driver-side. Disconnect, clean contact surfaces thoroughly & reconnect. Oxidizing connection there can lead to whacky light behavior. I had a somewhat similar situation shortly before my car's first State inspection under my ownership.

I don't know jack about non-.036, but it could be a similar issue with the diesel.

Great advice for both the .036 and the .131

Klink
06-30-2014, 05:17 PM
If the checks noted above don't yield results, note that the headlamp switches are starting to fail in ways that cause symptoms similar to yours. Note especially the way your headlamp switch feels. It all of the detents don't feel crisp and positive, it may be about to fail altogether anyway. I've seen 4 failures this year alone. Another frequent enough occurrence is cracked solder joints inside the bulb failure monitoring unit.

Stevester 500E
11-11-2015, 10:38 PM
I have the same issue, passenger tail light not functioning.
I started turning the headlight switch to one side to the other, etc. It doesn't feel crisp.
I jiggled the passenger brake light connector.
The odd thing is now my turn signals and hazard lights don't work.

I haven't had time to troubleshoot anything properly.
I do have a hunch that some of it is do to a faulty headlamp switch.

My electrical problems started with license plate lights not working. I think the headlamp switch is the culprit for that too.
I just don't understand how the headlamp is related to the turn signals. I see some relation as the left and right parking lights are related to the signals.

Will any working w124 headlamp switch work in a .036 or is it .036 specific?

nocfn
11-12-2015, 07:53 AM
fits 59 models and 409 variants. about $56 from MB, don't waste time with junk for 30, it will last a year or so.

P/N 0005456204 (http://www.autohausaz.com/pn/0005456204) or Gainesville with no tax or shipping http://www.mercedespartsoutlet.com/oemparts/mercedes-benz-137/0005456204%20.html

gsxr
11-12-2015, 08:48 AM
USA rotary headlight switch changed as of 1990 when they added the rear fog. I believe all 90-up switches will interchange, but make sure the part number matches. Louis is right, just get a new one. I've had to replace that switch in two of my cars this year.

:shocking:

Stevester 500E
11-12-2015, 10:46 AM
Did you purchase thru your local dealership or is there a less expensive source?
Thanks.

USA rotary headlight switch changed as of 1990 when they added the rear fog. I believe all 90-up switches will interchange, but make sure the part number matches. Louis is right, just get a new one. I've had to replace that switch in two of my cars this year.

:shocking:

nocfn
11-12-2015, 10:53 AM
I posted the link for autohausaz and the cheapest of 5 online MB dealers, in this case Gainesville MB with no tax or shipping.

gsxr
11-12-2015, 10:57 AM
I used good spares from my parts cars, if buying new you'll need to hit up one of the discount dealers like Louis recommended. There are no aftermarket switches available (except Uro junk). MSRP $79 USD, $63 wholesale... $59 at Louis' link above.

:spend:

Stevester 500E
11-20-2015, 09:41 AM
Thanks for all the help. I purchased and received my OEM switch from MB of Gainesville.
Now the fun begins.
Does anyone have a link to the best DIY of a headlight switch R and R for a 1993 W124?
Thanks



I used good spares from my parts cars, if buying new you'll need to hit up one of the discount dealers like Louis recommended. There are no aftermarket switches available (except Uro junk). MSRP $79 USD, $63 wholesale... $59 at Louis' link above.

:spend:

Stevester 500E
11-20-2015, 11:07 AM
I installed the switch.
It fixed the right tail issue.
However, my turn signals are still not working.
My turn signals stopped working around the same time as my right tail lights.
I am not sure if that was a coincidence or?
What should I check before I order a turn signal-wiper switch?
In addition, the hazard lights don't work.
The wipers work so I am a little puzzled.


Thanks for all the help. I purchased and received my OEM switch from MB of Gainesville.
Now the fun begins.
Does anyone have a link to the best DIY of a headlight switch R and R for a 1993 W124?
Thanks

nocfn
11-20-2015, 01:45 PM
With a small flat blade screwdriver, you can gently prise off the end cap of the combo switch. It is spring loaded so be careful there (took me hours on my kanda and knees in the shop). The whole guts come out and most likely is caked with gunk. Clean off and rough up with wire brush and re install. You checked relays by removing them, roughing up pins-light dielectric grease, reseat? Oh, prise off initially on dash side so if you slip, you won't see it every time you drive.

Stevester 500E
11-20-2015, 01:55 PM
Signals are now working after I clicked on an off the hazard switch.
My only issues now are:

The cluster blinker lights to not flash, even thought the blinkers are working.
My hazard lights don't work when switch is activated. I suppose I should check the relays.
Will have to find out where the relays are.

Nocfn, thanks for your help.

nocfn
11-20-2015, 02:02 PM
Sure thing. Maybe the cluster just needs to twist the bulbs - might as well clean it all up there if you pull it. Remove negative battery cable first :shocking:

Stevester 500E
11-21-2015, 08:16 PM
I ended up getting my right tail light to work by replacing the headlamp switch.
However, the lower right bulb does not come on. I tested the bulb and the bulb is good.
I replaced the rear tail light assembly(the one with the light bars) with a known good one.
Any ideas?
My hazard lights still don't work. Show I replace the hazard switch?
Are these two issues related.
Thanks