Tuesday, April 29, 2008

Mercedes Wire Harness Defect

The Defect...

Mercedes-Benz made an engineering blunder of gigantic proportions when it decided to use an inferior and unsuitable material for the insulation on the electrical wires of their vehicles. This insulation prematurely disintegrates under normal use causing the wires it is designed to protect and insulate, to short causing many problems.Defective Mercedes Wire Harness, Photo 1 The company continued using used this unsuitable material for many years, even on replacements and repairs. It is not yet known how many vehicles are affected, but it is estimated the number exceeds 1.5 million vehicles manufactured after 1991. It is not a matter of IF the insulation will fail, but of WHEN.

The engine Harness and how a simple harness can kill people...

This harness contains hundreds of wires bundled inside tightly wrapped tape. The wires communicate information from the many sensors of the vehicle’s engine and accessories back to the computer modules. The modules use this information to regulate critical functions such as engine idle speeds, RPM, fuel mixture, fuel injection, ignition and many more..Defective Mercedes Wire Harness, Photo 2
When the information received by these computers is garbled or erroneous the engine will run rough, accelerate unexpectedly or quit altogether. In addition when the wires short it could cause engine fires, sudden stalls on the highway and other failures that could cause death or serious injury.

Repairing these defects have been a bonanza to Mercedes Dealers, the typical cost of a harness exceeds $2,500, in many cases much more due to collateral damage (see below)... Most of the “repairs” were made with the same defective wires, so a few years later the failures reappear. Innocent victims have forked hundreds of millions of dollars to repair a safety defect that should have been covered by the company that created the problem, erroneously thinking that if the vehicle is out of warranty. Mercedes, aware of the seriousness of the problem, selectively and quietly replaced the harnesses at no cost only to the loudest complainers. They refused to effect a safety recall presumably due to the huge number of vehicles affected.

It gets better...

To add insult to the injury, the very dangerous safety defect also causes collateral damage in other parts of the engines. The expenses of there repairs may exceed the value of the vehicle. The collateral damage extends to very expensive and critical components of the vehicle such as the various computer modules and ECU’s (Electronic Control Units) that regulate the engine’s operation and the microprocessor-controlled fuel injection system,Defective Mercedes Wire Harness, C280 Sensor including the PMS (Pressurized Engine Control) Control Unit, the Engine System Power Control Unit, The HFM (Hot Film Air Mass Sensor) control unit and many others. Replacing these modules cost in excess of $10,000 in many cases. The computer modules get fatally damaged by the shorted wires in the harness.

In effect, the vehicle self-destructs.

The question is not one of IF they will fail but of WHEN – All vehicles manufactured in those years (at least ’91-’96) have the defective insulation and will fail sooner or later, thus you can understand Mercedes’ reluctance to own up to the problem:


Here are some links to web postings on this problem:

Mercedes Shop Forum

Auto News

Google Answers - Mercedes Wire Harness Defect

What you can do about it...

File a complaint with the NHTSA (National Highway Traffic Safety Administration)
NHTSAThe NHTSA is a politically-controlled agency driven by... you guessed... politicians whose campaign cofers depend on the auto industry's donations, and no one expects them to do much other than keep track of the complaints filed. But, by all means, EVERYONE should file a complaint with them. Contact your state's representatives and attorney general and file a formal complaint as well. There have been several attorneys interested in taking the case to a class action and this might be the final solution to ensure Mercedes-Benz assumes responsibility for its negligence.

Safety Defects have no statute of limitations. This has nothing to do with warranty, it's an engineering error that creates a potentially hazardous condition (engine fires, sudden stalls in highway traffic, stranding in dangerous locales, etc). Mercedes is well aware of the problem they created and refuses to do the right thing which is recall all vehicles affected, not wait for the NHTSA to do it, nor count on naive customer/victims not to do anything about it erroneously thinking that the age of the vehicles is a factor.

Letter to Mercedes-Benz President about the wire harness safety defect.

Response letter from Mercedes-Benz disclaiming responsibility - The arrogant "got suck an egg" "...so sue us" boilerplate letter.

More Photos of the Mercedes Wire Harness Safety Defect

Defective Mercedes Wire Harness, Photo 3

Defective Mercedes Wire Harness, Photo 4

Defective Mercedes Wire Harness, Photo 5

Defective Mercedes Wire Harness, C280