w124 instrument cluster - wiring harness - PeachParts Mercedes-Benz Forum

darkman · #1 05-06-2011, 10:50 PM

Hi All,
Mechanic says I need a wiring harness because my instrument panel is dead.
Nothing works except the speedometer. He says the several of the wires are fried. Anybody know the price and part number?

And does anyone have any experience with this... anything else I should know?

vstech · #2 05-06-2011, 10:55 PM

unless you have a bad short, the 87 harness is pretty reliable.
I'll have a complete parts car in my lot SOON... and the harness will certainly be available.
I would hope the speedometer still works, as it's mechanical in the 124... I'd think the entire harness under the dash would need to be pulled... I'd go looking for the short that killed it before changing it though.
I'd also visually verify the harness was bad before changing it. the mechanic may be assuming it's bad because the 94+ harness is known to fail, and he's lumping odd problems into that diagnostic. the 87 harness does NOT suffer from the degrading insulation of the newer vehicles!

darkman · #3 05-07-2011, 02:00 PM

Thanks for the reply. The speedo is the only thing that does work.

The backstory...
I think the harness is actually fried. The mechanic called me to come look
at it after he pulled the instrument cluster.

It's at this mechanic because I previously took it to another shop because
my taillight wasn't working-- an issue I described awhile back in another
thread last year
w124 Headlamp Bulb Change Blows #3 Fuse

The tail light began to work in an off and on way that had all the symptoms
of a short. Problem was... I couldn't find it.

So I left it at a nearby shop to have them trace it. They called me and said
they hadn't located it but was sure it was in the cluster, but they didn't have
a removal tool. I'm thinking "the #3 fuse was the original culprit so the cluster
shouldn't even be a factor".

I got there and was told that my #5 fuse was also blown. I knew that wasn't
the case when I left the car. But I did notice that the battery was connected
to a charger, and asked him how he was doing electrical work with power still on.
He acted like that was an irrelevant question. So after a pointed discussion, I
took the car and left

(I had cluster removal tools in the trunk).

When I took it to the current mechanic, who I didn't tell about the previous
shop, he gave me the "fried" harness report.

He says the insulation on some of the wires was melted and it burned some
other wires. He recommended a replacement harness to save time and to
ensure that everything was safe.

If you do have a replacement harness, I'm interested. Just pm or email the
details to me. And any other thoughts you have on this will be appreciated.
Thanks again.

darkman · #4 05-09-2011, 11:38 PM

I went to the mechanic and took pictures of the burned wires and melted
insulation.

They connect to a plug that inserts into the instrument cluster:
photo 1 (harness-plug.jpg)

The plug goes into the instrument cluster here:
photo 2 (i-cluster-back.jpg)

Two other shots of the burned/melted wires:
photos 3 & 4 (cluster-wires01.jpg and cluster-wires02.jpg)

Does anyone know what the name and part number is,
where I can find one, and the price range...

Also whether I'd have to remove the entire dash to replace it or
whether it can be done through the space where the instrument
panel was removed?

Any other tips and info would help too.
Thanks

vstech · #5 05-09-2011, 11:52 PM

... it's the main part of the cluster wiring harness.
save the round connector. it gets damaged, and it's nice to have a spare. and the boot that holds the connectors in it.
follow the wires into the firewall. disconnect if possible, but I've not done that kind of work on the cars yet, so take pictures!

darkman · #6 05-10-2011, 12:48 AM

Thanks for this.
I did a quick check online to see where I can find the part. If
anyone has the part number, that will help.

I know I won't be able take pictures since the mechanic is going
to do it. He cries about his insurance if I try to go into the garage
area while work is being done.

I will update the progress with any info that might help someone else.
Again... thanks

babymog · #7 05-10-2011, 10:45 PM

It would be much easier to just replace the damaged wires one at a time unless many wires are damaged.

ashedd · #8 05-10-2011, 11:24 PM

I had several wires at that point melted as well.....

LONG story short, I had to rebuild a 3rd of the wiring harness. I had melted wires all over the place.

Here is what I found: AFTERMARKET stereo install gone wild. That is where the harness started to melt. The owner at the time kept blowing fuses, obviously

, so SHE(yes SHE) had someone put new fuses' wrapped in foil in the fuse block. I am surprised the car didn't catch on fire.

So the question is: do you have an aftermarket stereo? And if so, who installed it? Look at the cigar lighter wires specifically. If I were you, I would pull the fuse block and have a look behind it. If there are wires melted in there, like I had, then you have your work cut out for you.