C280 1994: wiring harness problem

Unfortunately a well known problem that's quite expensive to repair - lots of labor to remove and replace the harness. Some dealers have cited "smog" as a cause of the insulation's deterioration but it seems rather to be related to the new, more environmentally "correct," plastics used for the insulation.

I haven't heard of this problem on other brands - perhaps I need to listen harder!

Interestingly, an owner of a washing machine store told us that they have had exactly the same problem in washing machines (also made in Germany)...

When the arrogant customer service guy was telling me this was 'normal', I invited him to have a look at the wiring of my 13 year old Toyota Camry :-))

Luc K

Perhaps a bad batch of wiring( a LARGE batch apparently). Maybe they ran low and went to radio shack...

Marty

PS this seems to be 94/95 model years?

You can have a look at the wiring of my 18 year old MB as well. Looks like new. This is an exclusively early nineties problem IIRC.

Ximinez

Indeed, I know a lot of old MB's don't have any problem at all, that's why it's so stupid (and infuriating) to call this 'normal'... I found various years. It's at least years 94 and 95 (except late 95)...

Luc K

I think it's a general tendency of dealers to downplay common problems or pretend that you're the only one plagued by them. They probably got away with that before the Internet...

Ximinez

I have the problem on my '91 w140 (European) as well. But only on the part of the wires near the engine, i.e. the part exposed to higher temperatures.

I have seen the same on a '95 Ford Mondeo.

It is not seen on older cars (my =B487 w201 for example, so probably it is due to new materials used in that period. Well, we don't now yet about newer models.

Jens

Paul McKechnie wrote:

While reading through the different reports I found, it looked as if the first problems surfaced in Australia in 1999. The high temperatures seem to accelerate the process...

Luc K

I had the same problem with my 1994 C280. After 5 years, the wiring harness was the cause of major problems with acceleration and cylinder firing. The dealer said it was due to Los Angeles smog. I looked at the service rep in the eye and said "yeah, right".

I think correleation between [average environment temperature] and [number of years elpased before problems occur] is higher than with [smog] and [number of years] :-))

Luc K

Does anyone know - when you buy a new harness - whether it is made from better materials with longer expected life?

Jens