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MERCEDES26
03-13-2012, 10:19 PM
I am posting this for interest sake.

I have just completed my own successful rebuild of a 92 500E wire harness rebuild. What an experiance...!

Here's the scope. I own 2 500's a 92 and a 93. The 93's harness went crook about 3 years ago and I bought new one for about $650 from the dealer and replaced it. Then late last year (2011), I decided my 92 should be replaced and the dealer wanted $800. So, I pulled both harnesses from both cars to see what the difference was and look into what I could do.

After metering out both harnesses I found the difference between the two. Basically everything is the same execpt that the common wire for the cam senosrs and the fuel injectors between the 2 is configured differently but I suspect with the same result at the end of the day (see attached self made diagram pictures).

I set about pulling the 92's harness completely apart. It was bad....and I mean evil bad....see picture...!

First I measured accurately every wire, terminal, and insulation terminal point thereby mapping the original. I took heaps of pics as I disassembled the thing.

I then went to a wreckers yard and bought for $5.00 a late model Volvo engine harness that had all the same wire colors I needed. I ordered new JPT male and female pins and wire seals from Bmotorsports.com for $35.00 and then set about doing some serious reconstruction.

I used the the original wire conduits and plugs where I could. They came apart and desoldered fairly easy. I used a self made grinded down wiper blade bracing strip to unhook the existing pins from the multi plug and fuel injector plugs. For the MAS 5 pole plug and the cylinder head water temp 4 pole plug I had to carefully open these with a Dremel along the seam lines.

Just for the record I experimented with an old plug by opening it with a Dremel and then resealing it with a thin layer of JB weld epoxy. I drilled very small angular channels into either halves to provide an anchor for the expoxy and set it gently in a vice for a few days. I then took it out and literally beat it with a hammer to see where it would break. Well, the plastic broke before the epoxy seall came apart. So I felt comfortable that a resealed plug will hold although I will check on this on regular basis.

Anyway, at the end of the day I managed to rebuild a harness that works perfectly, has all the water and environmental protection as best I could replicate and it cost me no more than $60 in materials (with sealants...no silicon..!) and a good few hours of pullig and soldering wires. It was fun...!

See the attached pictures.

What the hell....it worked.

gerryvz
03-13-2012, 11:54 PM
Wow -- impressive work! THanks for sharing. I'd love to have you start a gallery of close-up photos of your dilapidated wiring that others could add to.

:allhail:

Ron500E
03-14-2012, 12:08 AM
+1 actually +2....

What "late model Volvo" did you source the correct color wire from may I ask? I have been trying to find certain colors (don't ask why) but have been unable to.

I know that Volvo, BMW along with Mercedes (and probably others) used mostly Leoni wire (cable) as well as Gebauer and Griller but I thought the wire colors were up to the individual companies.

Thanks

Ron

MERCEDES26
03-14-2012, 12:10 AM
You bet Gerry...!

Let me gather my stuff together and try and get it in an order of santiy..!...for others to contibute.

Watch this space...!

MERCEDES26
03-14-2012, 12:22 AM
+1 actually +2....

What "late model Volvo" did you source the correct color wire from may I ask? I have been trying to find certain colors (don't ask why) but have been unable to.

I know that Volvo, BMW along with Mercedes (and probably others) used mostly Leoni wire (cable) as well as Gebauer and Griller but I thought the wire colors were up to the individual companies.

You know I just don't know. I just asked the wreckers yard to show me their scrap wiring bin and he led me to an area where ther were plenty. This particular harness (after pulling through piles of the stuff) was attached to some engine plugs and stuff that had Volvo labels on that had dates stamps of 2006. Most of the wire colors were either exact or very close. The assistant was close to useless (not his fault) so I was on my own. At the end of the day I was looking for wiring guage and coloring that would be the same of close enough for me to build a harness that I could map out and understand while building it.

bing
03-14-2012, 03:05 AM
:worthy::worthy::respekt: shit..+ 3 on this!

philnor
03-14-2012, 05:29 AM
Hats off to you sir!!!

Well done. Liked the way you went about it

Phil:triumphant:

zman
03-14-2012, 08:47 AM
Very impressive. Would you be interested in rebuilding another for shits and giggles. :)

samiam44
03-14-2012, 10:00 AM
Awesome! FYI,. When aerospace companies layout a harness to build. They basically have a 4X8 sheet of plywood(or larger) and a whole bunch of nails(think chanels with the runs layed out. That way you can put the correct length wires down. Leave a little excesss, bundle(they zip tie it together tightly) and then but the connectors on. If you made the board with all the paths.. then it would be quite simple to do a second board.
How long did it take you?

gsxr
03-14-2012, 10:52 AM
That is awesome. (Oh, and +4).

1) Some of the colors are different on the 1992 wires, btw... no idea why MB did this, except to confuse us.
2) The 1993 and 1994/95 harnesses are identical (same part number).
3) Your wiring diagrams are fantastic. Do you mind if I post these pics on my site in the M119 harness section?
4) As mentioned above... any idea how many hours you have into this?
5) I think I recognize one of your cars... looks like the Garnet Red / Black 1992 that was for sale on AutoTrader in early 2009 with 95kmi, correct? One of my favorite color combos. Droooool.


Thanks for the post & photos!!

:deniro:

Glen
03-14-2012, 11:24 AM
Just echoing what everyone else said, Wow! Great job.

kubasz
03-14-2012, 11:58 AM
Hi hello

I did my wiring harness too. It was already rebuilt one but it looked bad. It's an easy job if you will crimp all common wires from injectors. I did it harder way and soldered everything. I used 0.75mm2 silicone insulated CU wires for all sensors and injestors and from soldered junction point to plug i used 1.5mm2 wire. it works fine and all wires fit now in this original tunel that goes on fuel rail. I was impatient and used one colour for all connetctions. Then put self shrinking tubes and self bonding tape. The most difficult point is main connector. The enterance for wires was originally filled with glue so be coution at this point. It's easy to break the whole connector. Photos are showing some stages of my work but later i had to order some missing connectors to be 100% finished.
My car is '92 but i was not relying on any online diagrams and made one by myself. I wish you all 500E drivers to build engine wiring harness by yourself and save 9/10 of prise of a new one from dealer. :)

MERCEDES26
03-14-2012, 12:35 PM
Thanks to all for kind words....appreciate it.

By all means...please feel to post/distribute whatever you need or find interesting....that what this is all about...enjoying the car. If you think I can refine the diagrams just let me know. I am working on trying to tidy them up. Okay so the 94 was the same as the 93 harness. That is good to know.

How many hours.....at a guess as I did not too much attention to time.....it took me about a day to mearsure and map out the harness and meter it out and get the diagrams going. Say 10 hours for that. But that is done so need again. Then the dissassemble, with coffee and picture shot breaks, making the pin extraction tools and general fiddling....say another day. Another 10 hrs. I spent time during the week looking up pin and connetor suppliers, looking for wire etc. I guess once I had all my parts, I had thing done and back in the car over 3 or weekends.

So all in all...say about 60-70 hours....but it is my hobby so I didn't mind the effort But now that I have done it....I know where everything goes and the sequence of reassemble....I can cut that in half. Rubik's cube has nothing on the reassemble sequence of this thing....! You need to keep your wits about you and have to make sure you get all the wire conduits and sleeves on in the right sequence before attaching end plugs etc...or you end up starting again...and that is if you care about the quality of the end product too. The tricky part was the the main plug and the multi crimped terminal for the injector/cam sensor wires. That crimp is right up near the main plug in the sleeve. Anyway I am trying to put some details together for a future info thread and will explain in more detail.

Yes that is the same car...original owner was Bob Beltz. I am 3rd owner. I posted have some nice shots of it under the articles forum last year.

MERCEDES26
03-14-2012, 12:53 PM
The plug.....I contacted Delphi who make the large plug to see if I could get a new one unassembled. They found the plug in their system with the part number I gave them but said the product had a patent on it by MB and they could not sell it to the public. I actually called again a few days later to see if had I any luck with a different person....but same answer...NO WAY...!

So hence I had to learn how to pull apart mine. That main plug is desigend to take a nuclear explosion...but once you begin fiddling you find hidden traps like the all the gue stuff. But if you study the thing first there are tell tale signs as to what is possibly going on in there

But....good job to you too..! Yeah I wanted the harness to look original so I was very careful on disassembly to keep all wire sleeves etc....patience is key. And actually there are of very good quality anyway.
Thanks

MERCEDES26
03-14-2012, 12:55 PM
Thank You sir...!

samiam44
03-14-2012, 01:34 PM
Does it reallly matter if the wiring color is the same? If your not hung up on original colors, the MIL teflon(really something else but similar), silver tinned wire is *NICE* stuff. It's a little thinner than standard wire(od of the insulation).

Ron500E
03-14-2012, 01:38 PM
The plug.....I contacted Delphi who make the large plug to see if I could get a new one unassembled. They found the plug in their system with the part number I gave them but said the product had a patent on it by MB and they could not sell it to the public. I actually called again a few days later to see if had I any luck with a different person....but same answer...NO WAY...!Thanks

Had the same problem, most connectors (Plugs) are AMP which became Tyco which became TE Connectivity assembled by either Leoni (now in Poland) or Delphi (Spain) while most contacts are, as you mentioned JPT (Junior Power Timer). The contacts standard .096 inch with 5mm spacing. The wire are all 0,75mm2 with the exception (I'm using my memory here) of 2 which are 1,5mm2. The round 2.5 and 4mm Plugs and Pin Bushes are available through any MB dealer or Herth & Buss in Germany.
The connectors are a pain to disassemble but a few "cut to size" popicle sticks and some clay modeling tools helps while the contact removal is aided by a cheap (under $20) tool that looks like a minature tuning fork.

I contacted Leoni about buying some wire and they have a minimum order, per colour and size, of 19km....

Kind Regards

Ron

MERCEDES26
03-14-2012, 05:25 PM
Does it reallly matter if the wiring color is the same? If your not hung up on original colors, the MIL teflon(really something else but similar), silver tinned wire is *NICE* stuff. It's a little thinner than standard wire(od of the insulation).

No it does not matter in the technical sense of things as long as you accurately make a record of what colors you used where. Here is the problem....one day you sell your car and the next owner takes it to MB for some work that involves checking a componant or electrical connection associated with a service on the harness. If they happen to look at the wiring code to make sure they have the right circuit someone is going to scratching heads....!

jano
03-14-2012, 05:44 PM
Do they really check by color, though? I've never done that, always with the probulator, I never considered there was some standard to wire colors.

MERCEDES26
03-14-2012, 06:24 PM
Had the same problem, most connectors (Plugs) are AMP which became Tyco which became TE Connectivity assembled by either Leoni (now in Poland) or Delphi (Spain) while most contacts are, as you mentioned JPT (Junior Power Timer). The contacts standard .096 inch with 5mm spacing. The wire are all 0,75mm2 with the exception (I'm using my memory here) of 2 which are 1,5mm2. The round 2.5 and 4mm Plugs and Pin Bushes are available through any MB dealer or Herth & Buss in Germany.
The connectors are a pain to disassemble but a few "cut to size" popicle sticks and some clay modeling tools helps while the contact removal is aided by a cheap (under $20) tool that looks like a minature tuning fork.

I contacted Leoni about buying some wire and they have a minimum order, per colour and size, of 19km....

Kind Regards

Ron

Thanks Ron...yip as you say the wires are mostly .75mm and the 2 common returns for the injectors and cam sensors are 1.5mmm from the pig tail.

Below are pics of 2 tools which I made up from a grinded down wiper blade metal support strip to unhook the JPT pins. The metal is strong and doesn't bend easy making it ideal.....best of all it was free...! I too tried ordering wire but everywhere I went they wanted a minimum order. Hence the wreckers yard idea.

MERCEDES26
03-14-2012, 06:29 PM
Do they really check by color, though? I've never done that, always with the probulator, I never considered there was some standard to wire colors.

Well all MB wiring diagrams indicate the wire size and wire color code for circuits. So you can imagine if they are expecting a .75 Brown/Grey (BR/GY) when looking/cheking for something and they find a pink/violet or something...!

gerryvz
03-14-2012, 07:09 PM
Yeah, with the color and wheels on the car, I immediately recognized it as the Bob Beltz / MBCA feature article car but didn't say anything.

Sweetness !

amrik
04-28-2012, 03:50 PM
+5. I've also, with the invaluable help of this guide and schematics, just completed my wiring loom today, completely replaced every wire. Roll on Monday and we'll see if the car fires up. Fingers crossed.

amrik
05-05-2012, 03:54 PM
Whoopie the car runs like a dream now, but after the car had been running for about 10 minutes, I pressed the accelerator and it cut out. Tried to start it again and my friend told me there was a flash like lightening coming from the airflow sensor, what could that be?????? And it wouldn't fire up again, so i thought i would look into it tomorrow. I attempt to start the car today and it fired up first time with no problems.

Geoff
10-08-2013, 04:56 PM
I've also replaced the upper wiring loom with one i made, as the post above, the car starts up everytime from cold, but once it warms up to operating temps, it cuts out and will not start again until it cools down, can anyone shed any light on this ???????

MERCEDES26
01-10-2014, 07:47 PM
Hello...I am back on the forum after an absence. I have been relocating back and forth between CA, CT and CO....with my cars of course...!

Anyway...I can only guess....and sorry for the delay in responding....somewhere in your rebuild attempt, contact or insulation has broken down causing the fault. My original harness rebuild from the beginning of the thread...now nearly 2 years old works perfect every time every day. The car is in daily use and I drove it cross country CA to CT....CT to CO. No problem.