Mercedes-Benz Forum banner

41 - 60 of 253 Posts

·
Registered
Joined
·
5 Posts
MERCEDES WIRING HARNESS DEFECT

The ineptitude of this once mighty company is only matched by their arrogance and disdain for customers in handling this issue with the defective wire harnesses. Over 1.5 million vehicles are estimated to be affected and it's not a matter of IF but of WHEN your harness will fail.

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 stoppage in 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.

I am collecting a list of like affected owners to pursue action against Mercedes for this safety defect.

Contact me at [email protected]
 

·
Registered
2002 ML320
Joined
·
1,951 Posts
Don't post the same thing in multiple areas of the same forum
 

·
Banned
97'C280
Joined
·
3,184 Posts
corrosion on the wires comes from moisture that gets into the engine bay via rainstorms, etc...

as a preventive step, I plan to wrap the entire harness in electrical tape to keep the corrosion from building up in the first place. I don't plan on wrapping each individual wire since there is no need for that at this point. or ever....
 

·
Registered
Joined
·
40 Posts
Repairing Engine Wire Harness

I recently bought a 1993 300e mercedes a week ago with the same electrical problem. It was not running at when I got It. After a little time in testing the wire which I was told by th privious owner was the problem, I was able to start the car. The problem are the plugs connected to the ignition coils. I did the same repair and it works. Repair plugs kits are also available at the mercedes dealership. At first the parts department is advising me to replace the enitre engine wire harness at costof $1800 Canadian (wow expensive for on old car).The repair plugs will cost is lesss than $100C. I will give you update when i get the parts. Things to do is to strip all the tapes on the harness and thinking of replacing with tubes instead of retaping. This way I will able to recheck and repair wires as needed.
 

·
Registered
Joined
·
40 Posts
I woud suggest to use the split plastic tube to cover the wires. This is available in any auto parts store. This way you can recheck your wires without removing the electrical tape.
 

·
Registered
Joined
·
40 Posts
I also did repair my engine wire harness by raplacing each wire at a time. Splice a the ends to te plugs. Took meapproximatel 8 hours. this is is working only after office hours. Car start at first try.

I still have the idle surging.

My car failed aircare. I took my car to the repair shop for dignostic. The technician cannot do a proper diagnostic. The technician told me that there is still some shortage with the wiring.

I haven/t check the throttle actuator wiring yet.

I took a peak by cuttng a small cut the rubber casing. it seems that the insulators are gone too.

Is there a way testing wires for shortage?

Will the ECU be damage when there is wiring shortage?
 

·
Registered
Joined
·
40 Posts
Edumen said:
Made a new harness for my C-280, used the original connectors, spliced the wires (automotive heat ressistent) next to the plugs (connections) with solder and heat shrink tubing, took about 4 days to complete the project, car started on the first try, no trouble codes present, car is performing GREAT, car now has a steady idle of 550 rpm. Moral of this story ? You can DIY !
Ed

Removing the old one:



It's Off:



Repairing : Top of picture, Injectors and Coil plugs (red wire) repaired.



P.S It's important to take many pics, it helps solve repair and installation doubts !

I did the same procedure to my 300E. By replacing each wire at a time. I got replacement plugs connecting to the ignition coil from MB. Car started the first time. However, I still have the idle surge. I have not check the throttle actuator yet.
 

·
Registered
1996 Silver C36
Joined
·
543 Posts
raul21263,

You are one impressive auto electrician!

Rebuilding a C202 wiring harness? Thanks for the photographs and information sharing, but as far as I am concerned, your skills far surpass any that I could achieve!

Cheers,
OzC36
 

·
Registered
Joined
·
13 Posts
Anyone interested in a harness re-build service? I have been doing automotive electrical for the last 16 years, and I am a 1st class certified MECP technician.

I have all the supplies to do this, and i ONLY use solder and heat shrink tubing, NO CRIMP CONNECTORS!!!

Would $300 per harness and about a week turn-around time be decent?

What do you guys think, im just trying to help....
Are you still offering this service?
 

·
Registered
Joined
·
2 Posts
Don't know if anyone else found this, but I have a 1996 C280 and found that the 4 wires feeding the cam sensor, crank sensor and 2 knock sensors were bad. Any of these 4 will not let the car start. I found that you can buy the cam and crank sensors with wire from MB for $22, so I bought 4 of those and 2 new knock sensor plugs and was able to replace the defective wires. My car is running fine and I have saved $1500 for a new harness, for about $100 cost. I checked the other wires and they seemed good. I re-wrapped with foil tape and 3M 130 tape. All good so far.
 

·
Registered
91 500SL, 93 600SL, 95 S600 coupe, 97 S320, 99 ML430, 2003 CL600, 94 SL600, 97 Kawasaki 1100 STX
Joined
·
135 Posts
I had bad wiring harness in my 1992 500sel w140 body. I took it off and rerun every wire one at the time. I bought wires and heat shrinking tubes at Autozone. I soldered new wires at very end of plugs, some plugs can be opened and one can solder the wire directly to plug terminal. Main computer plug had to be cut open on top to get access to old wires. It is pain in the a** to repair old and broken harness. Insulation falls apart in your hands and falls all over working area. I tried to break off almost all of the remaining insulation. It took me around 8 hours to repair whole wiring harness. Car started at first try and never stalled once ever since.(It used to stall when driving over bumps)
 

·
Registered
Joined
·
1 Posts
I just replaced the wiring harness on my 1995 c220 as a DIY project. I researched the forums before I started. It was much more difficult than I expected. Here are some things that I learned about this project. I am going to refer to wiring harness legs as front-up, front-down, rear-up, and rear-down. There is also a middle leg which presents no problems.

The front-up leg connections are not difficult. You will need a female torx socket to secure the ground connector.

The front-down connections are difficult. You will need to remove the power steering pump to get to the three prong connector on the ac compressor. To remove the pump, you have to remove the v-belt and the pump pulley. You will need a large screw driver or pry bar across two of the bolts to stop the rotation of the pulley as you loosen the third bolt. Do not completely remove the bolt until you have loosened all of them because you will need it to leverage across to loosen the other two. With the pulley removed you will see the lower bolt which needs to be removed. There are two on front and one on the back (the down-front leg is right in the way of the rear bolt and will need to be moved). To remove the old harness you will need to cut several plastic ties which bind them together. The wires that head to the rear of the vehicle are bound by a strap that can best be reached from under the vehicle. To reach the knock sensor, it is best to remove the oil filter and cap. With small hands you can reach under the manifold to remove and replace it. The oil pan indicator runs straight down and is not difficult. The other leg of this wire goes back to the starter solenoid. You will need to get under the vehicle to reach the starter solenoid. The vehicle will have to be on jack stands at a minimum. I used the oem jack from the trunk and completed the job, but it would have been much safer and easier with better positioning of the vehicle. This is a 10mm nut which is virtually impossible to reach. I backhanded a nutdriver as I laid horizontally under the vehicle. It took luck and patience for me. The longest lead from this leg goes to a large plug just behind the ABS in the very front of the driver front panel. To remove the old harness, you need to lift the complete plug assembly up so you can see the track that the side pins must travel to free the plug. Under the entrance to plug, there is a U shaped strap that when pulled out about a half of an inch, it pushes down on the bottom of the plug. I think this is some type of locking mechanism but I never completely figured it out. I pulled this out, then guided the top part of the plug along the Z -track to free it. On my car, the most distal part of my new harness did not have the end part of the plug which feeds another type of harness. You will need to disassemble this and reassemble it into the new harness plug. This was not difficult.

The rear-down leg has a large connector that wraps around and underneath the manifold and is bolted high on one off the struts with a 5mm hex bolt with a 10 mm nut. These will freewheel if you don't control both sides. You have to get to it to remove the old harness and get to the male side of the connector that you will need for the new harness. I worked from below, but once you know where it is, I think you can work from above by removing the hex bolts on the back strut and pulling the freed wires through the orifice between the struts to unplug the connector. I think this connector goes to the idle control actuator which sends its wire down between the first and second manifold tubes. Now, I think it be would be easier to make this connection on top of the manifold. I don't know why it was routed this way originally.

The middle up and rear up legs are straight-forward.

I am somewhat embarrassed to say that it took me about twelve hours to complete this project. Had I known what I was facing, I would have walked away in cowardice. Fortunately, everything works.

My final thought is that I am discouraged that this $730 wiring harness is really the tip of the iceberg. The new harness replaces everything with an end connection, but the opposite side of wire-to-wire connectors have the same insulation degradation issue as the harness. It would seem that eventually, things will short out, and every wire in the vehicle will eventually need to be replaced.
 

·
Registered
Joined
·
5 Posts
I have a 94 600 SL V-12 with all the problems I have been reading about in this thread. Has anyone any experience with DIY engine harness repair on one of these. I'm new and a little nervous about this but since my car is what they call a "grey market" car (built for Europe and imported to the US) I think recycling my harness is the safest alternative even with my lack of experience. Any Advice or suggestions would be appreciated!!
 

·
Registered
Mercedes Benz C280 1995
Joined
·
120 Posts
Hi Guys

I had a problem on my 95 C280 (RHD) in regards to surging at high temperatures. There where also major vacuum issues. the cause of the vacuum issue was a crack in the vacuum junction by the fuse box. I fixed the crack and as i was putting everything together when i noticed a Bosch module 0280101008, that was not plugged in correctly. After fixing the crack in the Vacuum junction i started the car and took it for a drive. Not surprisingly the Tranny worked better the car ran smoother and almost everything worked. But the car was still running rich i plugged the Bosch module back in and it seems that the car is running a bit more lean, can any one tell me what this module does. As for the Wiring harness on mine, my C280 has 267000 Kilometers on the clock and only one or two wires have showed sines of cracking but they are not falling apart yet. I am keeping a close eye on those but for now they still seem good. I think the only difference between my car and most of the other people posting here is that mine was build in Port Elizabeth in South Africa.
 

·
Registered
2003 S430 Sport Edition
Joined
·
1,326 Posts
The MB tech showed me how to detect a faulty spark plug wire. When you start your engine listen closely for a ticking sound from one of the coils. His ecomendation is to replace all six wire and check the coils and spark plugs.

I have two of them making this sound and sometimes they will fail on high speed. From the Netherlands i order the complete set which comes 6 spark plug wires plus the two on top of the coils and the ones under the coils. That's a 24 wire engine harness from Bosch for Euro 220,00

Here at the local dealer they are asking only for one spark plug wire about Euro 60.00 each. One coil cost here in Euro 566.05 each.

Eddie
 

·
Banned
97'C280
Joined
·
3,184 Posts
I have a 94 600 SL V-12 with all the problems I have been reading about in this thread. Has anyone any experience with DIY engine harness repair on one of these. I'm new and a little nervous about this but since my car is what they call a "grey market" car (built for Europe and imported to the US) I think recycling my harness is the safest alternative even with my lack of experience. Any Advice or suggestions would be appreciated!!
when I bought my C280 I immediately wrapped my harness in electrical tape and haven't had a problem with my harness whatsoever, thank God.. the MB harness is wrapped in some sort of cheap paper-like tape and when your car fails it's becuz the wires are touching something hot and causing the failure. or it could be corrosion when water gets in there. the electrical tape is more insulation against the wires getting too hot and wet. plus it emits this sticky resin that further keeps the wires from corroding.

just my philosphy
 
41 - 60 of 253 Posts
Top