henko

Fellow SL600 drivers - it has come to my knowledge that early SL600's (1994 thru '96) have a fatal issue with the main wiring harness. This is due to MB's choice to use an insultation around the wires that withers away with time.

Our local dealer here in Southern Orange County,CA (take your pick, there are two) wants $13,000 to fix it. The reason is they have to remove the dash board, the interior, etc, etc. Obviously very time consuming, so it's not their fault that they want to charge $13K, by any means.

However, I would like to claim that it is MB's problem. When they sold the car I'm sure they didn't inform the buyer that the car was only designed to last about 10 years or 100K miles. This was a $100,000 car at the time, and putting that kind of cash in a car the expectation is that it will function properly for at least twice as long provided all service has been done. So I would like to have MB USA take responsibility for the repair.

So far, I have been able to locate one other member on this forum that has successfully had MB USA pay for the repairs. I would like to hear from anyone else who has had this problem, and learn about how they resolved it.

https://mbworld.org/forums/showthrea...wiring+harness

https://mbworld.org/forums/showthrea...wiring+harness

http://www.mercedesshop.com/shopforu...wiring+harness

12 horsemen

I bought my 1994 sl600 as a hobby car. Runs Great I would like to avoid issue by replacing it. Q? Is it possible to remove and rewire the harness with high temp insulated wiring or snip the wires individually, put some high temp heat shrink wrap on each existing wire, solder and recover it? Or, does anyone know of a company that either sells or remanufactures the entire harness?

R.S.

Sold my 84 380sl (51k miles) in March because I had the opportunity to purchase a 95 sl600 with 27,000 documented miles. Before I actually bought it the two items that came up as problems were the two you addressed so if anyone had an idea on the least expensive way to fix in case of failure let us know. This is not my daily driver so if it needs a $13k wiring harness than the car will probably be parted out. A shame because this car looks brand new.

R.S.
triple black 95 sl600

12 horsemen

Came across an interesting mod. Check out www.v12uberalles.com. Might be worth a try.

12 horsemen

It's very sad when a company like Mercedes-Benz won't own up to what is an obvious poor choice of manufacturing material hand picked by Mercedes-Benz!!, (fire all those engineers and QA guys who let it happen!!)
My plan: step 1.Approach Mercedes and see if they will replace both the engine and transmission harness. if not step 2.) Put a shine on it. It already attracts a lot of attention as it is fill up a cooler, pitch an umbrella and park it right next to a Mercedes dealership on one of their busy days and in bright neon yellow write "LEMON (POS)" ask me why. With most Mercedes clientele not being idiots, I am sure to get a few enquiries as to why that finely kept shiny piece of machinery is parked there.
I don't buy the biodegradable story. A car like the R129 MB SL600 should have had the best minds, not the lowest bidder.

R.S.

I agree. I've never had a problem with mine yet so I'll keep knocking on wood and hope I get lucky. Mine is virtually shop room quality.

R.S.

blueSL

A failed wiring harness was the final nail in the coffin for my SL600 which is why I sold it. Faults, especially if they are intermittent are very difficult to find, the extreme heat in the engine bay makes things worse and, of course, with the wiring harness being one of the first things to go into the car, even repairs, never mind replacement are bad news.

Quadrobenz

I am currently having the wiring harness replaced in my 1994 SL600. It is slightly over 101k miles. I can recommend Oscar Casco, owner of MB-Class Motors in Mission Viejo for service. The price for this work is a fraction of the $12k mentioned. The replacement harness is not a direct fit on the 1994 so it requires modification.
TLR

R.S.

Tom,

Thanks for the info. My 95 is still under 30k and heat build up in the engine compartment is not a big issue, usual ride is 20 to 30 miles once or twice a week but I know the time will come.

R.S.

Does anyone know the precentage of cars that has this problem? Mine has seem to have any symtoms yet?

hollerbox

I replaced the wiring harness in my '94 SL500 at 98,000 km last summer. Had to replace several other very expensive components that were damaged by the faulty harness as well (control units, throttle actuator).

If I knew then (at about 95,000 km) what I know now, I would have replaced the wiring harness as a preventative measure rather than let it get worse and very quickly damage the expensive, non-repairable components.

R.S.

That is a great idea. Thanks for the advice.

R.S.

Quadrobenz

I had to replace one of the two throttle actuators and, I believe a MAF unit which were damaged by the failed harness. MUCH cheaper to do the harness as a preventive measure rather than wait for it to fail. Essentially all these harnesses will fail, I am told the most common time is between 90k miles and 120k miles. The type of driving apparently can influence the life of the original harness. The replacements are supposedly a US made product with different materials than the original and are not supposed to fail as the original harness does.

R.S.

Only have 30k but I think now rather than later. Thanks everyone for the advice. I'm sure it will save me heartaches and money.

Quadrobenz

I picked up the car this evening. I was able to examine the old harness after removal and the new style replacement harness. The copper conductors and the insulation have been changed. The insulation in the old harness literally cracked and split off the conductor when I flexed the wire. You could see bare conductors when the outer jacket was cut away. The old copper conductors were very flexible, contributing to the cracking of the insulation. The copper conductors in the new harness are extremely stiff, minimizing or eliminating the flexing during operation.
I did misspeak earlier. The replacement harness is made in Germany. The replacement cables for the throttle actuators are made in the US.

karlhausrealty

THERE IS A CLASS ACTION IN THE COOKER. NEED TO SHOW INJURIES IN AN EARMARK CASE AND IT'S A GO. THIS IS A THREE BILLON DOLLAR LAWSUIT AGAINST MERCEDES BENZ FOR THEIR SHODDY ENGINEERING.

PROBLEMS RANGE FROM SUDDEN ACCELERATION, STALLS ON THE HIGHWAY, SELF DESTRUCTION OF THE COMPUTERS, ENGINE FIRES AND OTHER VERY DANGEROUS SYMPTOMS. THERE HAVE BEEN NUMEROUS ACCIDENTS, MOSTLY SETTLED QUiETLY BY MERCEDES BENZ.

FILE COMPLAINTS WITH THE NHTSA AND COPY YOUR STATE REPRESENTATIVE.

LEARN MORE AT http://www.MercedesDefects.com

SRHsl600

Henko
I have the old harnesses, photos, repair tickets and a mechanic ready to relate his story and related vehicles that have experienced the same fate. My letter to MBUSA was set aside because of warranty time and mileage, inspite of issues mis-diagnosed by dealerships when the vehicle was under both the mileage and 48 month time element. My federal complaint forwarded to NTHSA was not to the level of recall because death or insurance related property damage had been part of the complaint.
Let the forum know about any movement on a class action.

karlhausrealty

The defect was known to Mercedes Benz. The defect causes sudden acceleration. Just like the UAW-driven prosecution against Toyota was enough to cause a widespread recall, the Mercedes defect is hundreds of times more dangerous and widespread. This has nothing to do with Warranty. It is a SAFETY DEFECT.

The fact that Mercedes has done little about it due to the billions of dollars it will cost evidences malicious contempt to the public and US Laws.

pleeson

Good luck with that one.
The cars are 16 years old now.
I suspect "Statute of Limitations" time has passed.

moslele

I, too, have a major engine wiring problem.

Sadly, I took and car to a place that managed to blow the engine control computer, too.

I have a source for the computer repair (at 1/10th the replacement cost from Mercedes), but have found no source for a new replacement engine wiring harness. (There's a used harness at ebay, but what's the sense in that?)

I would be happy to join in with others in an effort to convince Mercedes that they should pony up and correct this problem. I bought my car in beautiful condition with very low miles, believing I had a top-of-the-line, reliable automobile. Mercedes' reputation has plummeted in my personal view.

Please tell me who has a parts source, the best deal for a fix, and what I can do on the lobbying front with Mercedes.

Seriously irritated here in the Northwest....

Lee

Mike P

I have contacted my dealership..they claim they've never heard of the issue.

I have contacted MBUSA several times.....believe it or not, the highly skilled technical reps have never heard of the issue either!!! I hate the lies. I requested a courtesy replacement of the engine harness.....MBUSA will "consider" the case only if the harness is returned in a degraded state. The "mythical" problem can cause other components to fail(control units, throttle actuator and MAF to name a few). Keyword: "consider" means dream on.

I'm going to replace my harness BEFORE it precipitates further cost.....on my expense. I must be a valued consumer to get such great treatment. MBUSA could care less...pitiful. I'm open to ideas for action.

SL65,SL600(with 43 total miles),560SL(262 miles),E300D, 240D

SRHsl600

The other benz forum and this have many bloggers who have been greeted in like manner by the dealers and MBUSA. The two forum ( the other world won't accept me as a member, too cheap to buy a life time membership, I think) should forward the blogs to MB, both in the USA and Germany.
The last class action suit I was a part, turned to be wonderful for the legal system but only pennies on the B of A dollar, so that is not an outlet worthy of my time. Community ( blogs, Angie"s List, et al ) action to let the dealers know, that we know about their short falls may be the only outlet
As before, ready with a boxes of parts to show the court!

hervemarco87

Hi

I have the same problem with my SL 600 1996 my ASR light come On Mercedes told me perhaps you need to replace the wire harness , my car cannot pass the smog , my mechanic told me your computers need to be replaced , Base module computer, left computer and perhaps right computer, I already replace a lot of stuff like control valve. I think I have the same problem like everybody , If someone can give me some address to replace the harness and to repair the computers for a good price , let me know.
thanks you
hdomange87@yahoo.com
mission viejo California

hervemarco87

I have a SL 600 1996 I am in Mission Viejo how much did you pay?
thanks
herve
hdomange87@yahoo.com

MB_Fahrer

I just bought a '92 600sel with 36k miles, I believe this car has the same problematic wiring harness as your SL's. Should I change the wiring harness just as a preventative? I should mention I might be pulling the engine and installing the 7.3L V-12 which would give me further incentive to do anything I can to prevent electrical issues. What do you think?