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Hi All
i just wanna share a project that will be started soon with my W124 E320 M104 engine.
I have been restoring this car since 2013 and im done with all the body works (upgraded to E500 with all OEM parts and EVO wheels), and now im exploring to enhance the electrical system.
It all started when i came up with the idea of having a 722.6 transmission on my car, i have been using a standalone TCU for 4 years and i didnt quite satisfied with it and now in order to get it right i need to install an OEM EGS and in order to make it work i need to upgrade the engine electrical and ECU to ME2.1 with drive by wire system and canbus communication.
I have a C36 engine on the way and hoping when im done with all the electrical upgrade, i can install the engine.
i have found a few parts from a non ASR 1997 C230 kompressor with ME2.1 which would be a great donor since it doessnt have ASR:
below is the parts that i found:
1. EGS and 3.27 differential with one abs sensor and complete with EGS wiring harness (having a 3.27 diff with a C36 engine would make this car quite fast)
2. Complete ECU to body wiring
3. ABS system from the same car and complete wiring
4. Complete ECU with keys from early 1997 E320 with ME2.1 and DAS2 (a 1997 C36 ECU with ME2.1 and complete keys would be perfect if i can find one)
5. Pedal position sensor, K40 relay, and all other small modules.
Now the main problem is how to integrate all this new electrical system to old w124 AUX FAN, AC system, fuel pump relay, instrument cluster etc and if possible still use the E320 ABS system.
i want to make it as simple as possible so i would only install modules and wiring that is required to get the ME2.1 and EGS system running normally.
From my point of view, these are the benefits:
1. Complete engine diagnosis using Star (not available on older HFM)
2. 722.6 transmission with OEM EGS (fifth gear and lockup) please note that small NAG has lower gear ratio than 722.3, this would be greatly increase acceleration
3. Drive by wire system
4. ME2.1 is Piggy back friendly system unlike the HFM so i can easily tuned the ECU to match any upgrades in the future
5. By installing the ME system, it opens the possibility to install an M113 engine and having a V8 on RHD w124 (no plan yet but possible)
Please check below pictures and i hope somebody can share their experiences dealing with this kind of retrofit.
Any help is much appreciated
So i got the c230 wiring out now, and starting to mark the wires one by one according to wiring diagram.
i got trouble with this blue plug, it is suppose to be connected to ABS pump, but on the car it is actually going into the cabin.
no idea where it goes, anybody have seen this kind of plug?
also im looking for RPM signal from the ECU to srive the tachometer and w124 Climate control relay.
this is the mistery plug, its coming out from ABS control unit
more progress now, i managed to separate all the wiring that goes into the ECU from the body harness, and surprisingly almost all wiring coming out from the ECU is routed to the K40 relay, ABS and EGS. the other bunch of cable is just lighting system wiring, washer, wiper etc.
the only wire that needs to be connected to the w124 body harness is just the starter wire, 12V, ACC, Ground to K40 relay.
its pretty much simple wiring.
now im waiting for my camshaft adjuster to arrive. the ME ECU read different kind of signal from camshaft so i ordered a 1997 camshaft adjuster.
i also installed a 3.46 diff from 1997 S320, the 3.27 diff from c230 is 185mm, while the stock e320 has 210mm diff.
i use the EGS that i got from this c230 on my supercharged E320 with 3.27 diff from s320 with perfect result.
now i have to find the correct EGS to work with small NAG and 3.46 diff.
Finally, all the ECU body wiring, ABS, EGS, K40 is in, time to plug in star to see if it can read all the module and live data.
i have to make sure star can read all these module before going any further.
look really cool to have a computer box with 38 pin diagnostic plug on w124
An update, finally i plug in the star diagnose after hours of wiring repair, i spend most of the time removing all the non-OEM wiring done by other shops. mostly audio wiring and alarm.
now i have all the wiring done according to mercedes color codes and diagram.
here is the screen shot of the star, ECU, DAS, EGS and ABS modle was detected allthough they are not connected yet to the sensors.
But I am sure that all the wiring is correct and CAN-BUS communication between modules are connected. hopefully i can start the car next week and test the car.
some screenshots from the star
DAS is all OK, no security triggered EGS module now connected, i can tell that the whole canbus system is working now
Finally done with this conversion, now my car has 722.6 transmission with TC lock and OEM TCU. completely transform the car, it shift much smoother and it has better torque due to gearing ratio on the 722.6.
it takes a while but im completely satisfied with the result, much more responsive feel, smoother engine, much softer throttle pedal ( just list all the newer benz), supersmooth shift from P to R or N to D, and the best part is I can diagnose my car with STAR.
now im waiting for my 1997 C36 engine to arrive, super excited!
Just wonderful.
I have four M104 3.6s in stock.
With HFM, 3.6 has different ECU than 3.2 or 2.8.
Igniters in the unit differ from others.I know it works with non AMG ecu but it makes difference at high rev.
Is ME capable with this ?
Last edited by staff virage; 01-20-2020 at 07:25 AM.
Finally done, C36 engine is in with ME 2.1 ECU, drive by wire throttle, 722.6 transmission with OEM EGS 51, CAN-C networking with ABS, STAR DAS2 diagnosis compatble with 38 pin plug.
from what i found, 1997 ECU (ME2.1) for C36 is the same with most E320 or S320 with ME2.1.
the car feels much much more powerfull than E320, i cant complaint.
i havent got a chance to dino yet but i am very satisfied with this build plus the 722.6 transmission has much better ratio than 722.3 which helps acceleration on 1st and 2nd gear plus the fifth gear and lockup features is amazing.
Hi, very cool project and congrats for succeeding! Your car looks very, very awesome! I want do the same you did: C36 engine + tranny into my 124 E320. Now I am really inspired by your work using all the W202-OEM-parts like modules & wiring. My thougths are the same: seperate all the unnecessary stuff from w202's wiring harness. But my donor C36 has ASR traction control. Here are my major doubts:
-ASR traction control system very similar to normal ABS, differences: wheel speed sensors for both rear wheels instead of single sensor mounted in diff housing - no problem, swap to w202 ASR rear wheel knuckles, they should perfectly fit into w124 axle. -ASR/ABS pump uses 6 brake lines - no problem, add a second rear brake line -ASR system uses both front wheel sensors or all wheel sensors for vehicle speed data - Problem when using w202 front abs sensors on w124 wheel knuckle. Does they fit? How did you solve it? -w202 Tachometer/instrument cluster is different - did you get all important wires from the w202-wiring into the w124 instrument cluster?
Rest should be easy work, it's not my first m104 swap but the first using other platform's wiring and modules. I hope to hear from you.
Hi, very cool project and congrats for succeeding! Your car looks very, very awesome! I want do the same you did: C36 engine + tranny into my 124 E320. Now I am really inspired by your work using all the W202-OEM-parts like modules & wiring. My thougths are the same: seperate all the unnecessary stuff from w202's wiring harness. But my donor C36 has ASR traction control. Here are my major doubts:
-ASR traction control system very similar to normal ABS, differences: wheel speed sensors for both rear wheels instead of single sensor mounted in diff housing - no problem, swap to w202 ASR rear wheel knuckles, they should perfectly fit into w124 axle. -ASR/ABS pump uses 6 brake lines - no problem, add a second rear brake line -ASR system uses both front wheel sensors or all wheel sensors for vehicle speed data - Problem when using w202 front abs sensors on w124 wheel knuckle. Does they fit? How did you solve it? -w202 Tachometer/instrument cluster is different - did you get all important wires from the w202-wiring into the w124 instrument cluster?
Rest should be easy work, it's not my first m104 swap but the first using other platform's wiring and modules. I hope to hear from you.
Best Regards, Max from Germany
Whats the year of the donor car? This would determine what wiring swap would you need.
Front knuckle is the hardest part, but again what the year of the donor car?
My c36 engine comes from 1995, transmission and wiring is from 1997
The main reason why i use the 1997 wiring, is because 1997 cars has throttle by wire system, ME2.1 which is much more smarter than HFM, less wiring, compatible with SDS, and offcourse the ultimate reason is the transmission. All 1997 cars has NAG1 transmission with electronic 5 speed and gear lockup. This will change the way the car drives so much.
For instrument cluster, RPM is from ECU, there is a wire that you can connect to the ECU for engine speed signal, fuel indicator (stock w124), speed is fron drive shaft (search on google how to swap electronic speedometers for w124/w126), oil level sensor (manually wired from instrument cluster to oil sensor), engine temperature (installed the w124 cooling temp sensor on the thermostat housing and wire it directly to the cluster, so the car has 3 sensor instead of 2)
My car has the 500E reiserechner instrument cluster, so its kinda more complicated, but the basic function and wiring is the same.
good luck with your conversion!
Hello Brabus,
tanks for your quick response. The donor C36 ist from 06/1997 with NAG1 tranny and DAS2. The reason about my concerning is because I am not sure the ME2.1 gets the right vehicle speed input when the swapped front ABS sensors do not work properly in w124 knuckles. In that case the ECU would fail all neccessary driving funkctions I think? Maybe I must do some work to the w124 front knuckles to make them fit. Did you leave the stock ones in your car os did you swap them to w202 sensors?
When you say speed from driveshaft - do you mean the speed input for ECU or a seperat input just for speedometer? (I'm going to use 400/500e electronic speedometer in w124 instrument cluster assembly).
Ok great, since you have a complete 1997 donor, you have to swap the ECU (the whole set with key and das module), ABS and EGS.
The front knuckle is the trickiest part, my donor car was from a 1997 with SINGLE REAR WHEEL SPEED sensor which is located on the rear diff, so i didnt have to change the rear knuckle. So it reads the rear wheel speed sensor from the differential.
now this would be tricky for you if you are planning to use 2 wheel speed sensors on the w124, since none of them comes with wheel hubs with sensor teeth (you should now what i mean) so they dont have mounting for speed sensors on rear wheels. But you can use differential from other mercedes that has two sensors on the differential, if im not wrong the 210 abs rear wheel sensors was located on the rear differential not rear wheel hub.
all differential on 90s mercedes are swappable, but you have to pay attention on the diff ratio that match the c36 EGS.
if i were you, i will check on your donor car and see if the rear sensors is located on the rear diff or wheel hubs.
Now the front part is tricky. The 124 original knuckles has 48 teeth (if im not wrong, i forgot the exact numbers), the EGS / NAG trasmission system only read 24 teeth to run correctly, again i forgot the exact numbers but it is half number of teeth compare to oem w124.
Luckily, w124 SHARE THE SAME wheels knuckles and Wheels HUB FROM R129!
so i bought a brand new wheel hub from 1997 R129 (that comes from NAG trannny cars)
The dimension and sensor teeth is correct with w124, the next challenge is wheel bearing.
I use the 124 oem bearing but it is loose to the wheel hub, i tried using the w202 bearing, it fits the wheels hub but it is loose on the knuckle.
I suppose if i buy the whole set of R129 knuckle and wheel hub, it will be perfect.
But i cant source any knuckle overhere, so i ended up buying just the hub and use the w124 bearing and make some bushing made of stainless stell to tightly fit the bearing into the wheel hub.
It is working perfectly, and since the bushing is so thin, it does not cause any vibration or whatsoever.
Given that you are located in germany, i suggest you to buy a used knuckle from a 1997 R129 cars complete with the wheel hubs (the sensor teeth is actually located on the wheel hub not the knuckle)
pay attention to the number of teeth on the wheel hubs! Old mercedes abs system reads 48 teeth (again i forgot the numbers).
the newer mercedes that use NAG transmission read 24 teeth.
But all rear differential from the beginning of abs system installed has 24 teeth, so thats why you can swap diff from other mercedes. Even all the mounting is the same. I swapped my diff many times from w140, w210, w202, they all works.(i did this just for trial and errors, playing with different ratios)
good luck!
Regarding the speedometer, yes you have to use 400e or 500e w124 electronic speedometers. Not the manual speedometers.
The speed signal on this unit is not from the ECU, it has it owns sensors on the transmission tail housing. But since you replace the tranny to NAG, so you would need to install the sensor on the drive shaft, just weld 4 metal teeth on the drive shaft and mount the sensors and wire it directly to the w124 electronic speedometer it will work.
You can search on google about this, there are many threads about upgrading to w124/w126 electronic speedometers.
Hello and thanks for your response!
At the moment I'm busy with parting out the donor. Last days I removed DAS, key reading coil and ignition lock. There is a wire going under the alcantara headliner to the infrared-light-receiver at the rear view mirror. I'm sure to swap the mirror too. Do you know wheather the infrared-light-receivers in the door handles fit to w124? I will find out...
I discovered ABS sensors on both rear wheel hubs at my donor C36. It should not be a problem to swap the rear hubs with sensor cables to w124. I'm sure this works because the rear axles are very, very similar, differences regard f.e. the axle width but the knuckle should have the same mounting points as w124.
Thanks for the R129 front knuckle tip, but I am sure you wanted to write "...The dimension and sensor teeth is correct with w202..."??? Would make sence because it has to fit with the w202 ECU and wiring.
Getting whole r129 knuckles with wheel hubs and bearings is not a problem here in G, but it's more pricey as w124 parts. These parts are the next gonna be purchased.
For now I'm sure it will work with the donor diff from C36 (2,85 diff ratio). So the whole w202 propulsion system will be swapped into w124.
Btw: is the NAG1 length identical with 722.369? I think so.
Speedometer is clear know, I read the stories about the four metal teeth welded on the driveshaft, absolutely horrible imho but it seems to work fine so it's worth the work. Maybe you can tell me which sensor do you use?
I didn't know the speed sensor in 722.3xx tail housing! That's genius MB work from the 90s.
With all that info and your help the project becomse much mor real! Tomorrow the engine is being pulled and stored. I need time to part out the donor and sell the rest.
Thanks for your help!
Last edited by Benzdriver91; 03-25-2022 at 06:06 PM.
You cannot use wheel hub from w202 (ive tried this, trust me), first you have a problem with the bearing, (inside the wheel hub there is 2 bearing), the kunckle shaft of the w202 has larger diameter so when you install it on w124, its loose and you cant tighten it, and the knuckle is longer on the w124. In my opinion, waste of time. Even so when you succeeded to modify it, then you will face another problem with the brake calipers position, and since the difference is significant you might have problem with the wheels hitting the shocks, and then event though you make this work, the width from tires to tires would would be narrower, and resulting in poorer handling.
so its not a worth all the effort.
just get a knuckle set and wheel hub from 97 r129 from a junkyard and be happy, if possible with the brembo brake calipers and disc (all plug and play for w124)
the length of 722.3 vs 722.6 has 5mm difference (a lottle harder to install the drive shaft later but shouldnt be a problem at all.
The sensors for the speedometer - you cant get if from w124 400e, 500e or 1996 w202/w210 (earlier version woth 722.3) on the tail of the tranmission housing therr is a sensor, a size of a thumb. Thats the vehicle peed sensor. It has 3 wires (ground-voltage-signal) very simple.
For rear wheel hub, i havr no comments since i didnt face this issue, my suggestion, take out both cars hub, and compare.
I Agree with you to use the c36 diff.
yes the wheel hub from 1997 r129 has the same sensor teeth vs 1997 w202, basicly all NAG use the same numbers of teeth. I capture and image from w202 wheel hub, notice the teeth, this is what we want for NAG cars.
The sensors on the w124 will not work on the w202 das system
Just use the oem w124 infrared system, remove rfid chip from the w202 key, and stick it to the w124 key remote. All you need is the rfid chip. It is located inside the key near the infrared light.
dont loose it, this will be your only one rfid chip.
Take out the whole alarm system from the w202, is jsut wouldnt work on w124
Just connect the das, keyring and ecu
Thats it to make the car run.
My advice, takeout the front wheel hub from both cars and compare. The w124 wheel hub is much wider around 2cm, only r129 hubs has the same dimension with the correct numbers of teeth.
Hello,
thanks again for your response. It's clear not to use 202 hubs & knuckles. I started to look for R129 hubs, but even in Germany difficult to find - and expensive. But I'm sure to find one.
One question about the tranny length difference of 5mm: did you measure that precisely? Do I understand right the 722.6 is 5mm longer than 722.3? Some idea would be to shorten the centering pins from tranny and diff for that 5mm (2,5mm each) for easy installation of drive shaft?
Tranny speed sensor is clear now!
Ok I will swap DAS, Key Ring and ECU from 202.
Some last questions: did you swap an ABS-ECU too? My donor does not come with seperat ABS-ECU, instead it has ASR-ECU which has a bit smaller housing than a normal 202 ABS-ECU. I woll show you some pics later. I think the ABS-ECU is integrated in the ASR-ECU on cars which are factory equipped with ASR. I also could not discover an extra ABS-ECU in the "ECU area" of the donor.
At the beginning of your thread you showed that mysterious blue plug which belongs to the ABS harness. Is that the plug for rear wheel ABS-sensor? My donor has the same plugs in foot rooms on both sides of the car. I don't know what do they connect?
Transmission crossmember: from w124 oder w210 or which one else did you use? Unfortunately my donor car's crossmember got damaged by an accident.
Best regards, Max from Germany (with the crazy Autobahn, yesterday I pushed my 93' E320 sedan to 220 km/h)
Drive shaft issue, shouldnt be a problem actually, but if you want to do shorten it, you can do it on the drive shaft, not on the middle of the drive shaft but on the tip that connects to the transmission or you can cut some of the drive shaft connector on the drive shaft joint. I end of up milling it 5mm shorter. I didnt meassure exact mm but 5mm is pretty accurate
ABS/ESP, yes they are combined in one unit. There is no more additional control unit except the one on the ECU box. ABS system consist of ABS pump and ABS/ESP control unit
For the blue plug, i forgot how i connect those, but telling from the wire color, it it can bus C (green and green/white), black/red should be R15
BTw do you have a complete diagram for w202 and w124?
Without wiring diagram, its going to be hell for you.
You should modify starter wire and other accesories like AC too and dont forget you have to move the battery to the trunk.
Just use the w202 main battery wire, the length is enough to reach the w124 trunk.
Hi, another possibility to get that 5mm would be to lengthen the chassis holes unterneath the engine mounts. There sould be enough room between radiator and engine. But that's not important anymore, I will find a solution.
At the moment I do not have any wiring diagram from w124 and w202. Do you have some? Maybe you can make a copy?
How did you modify starter wire? DAS module is connected to starter wire from ignition switch, I mean. And from DAS module the wire should go to the starter. In w124 the AC-system is just the AC relay and the AC-interface in interior. As I know the AC-system relevant information like engine temperature and AC-compressor rpm comes via engine wiring harness, regarding my w202 donor car. I think the K40 relay manages the AC-compressor in the w202? Then there must be the wires which I have to connect to w124 relay(s) and harness, haven't I?
Last edited by Benzdriver91; 03-31-2022 at 03:12 AM.
Dont bother about the 5mm difference, it will fit without any modification, just shorten the tip on the drive shaft joints, thats it
regarding the AC system, w124 AC only has one wires connected to the oem ecu, which is to stabilize the idle during ac on and off. The extra fan is a standalone system with its own temperature sensor and pressure sensor connected to the ac drier. So you dont have to do anything with the ac system. You have to install another temp sensor (w202) on the thermostat housing, becuase you cant the temp reading resistance is different between w124 sensor and w202. So just install two sensors, there is spare hole on the thermostat housing for additional sensor, very easy.
For the starter the das module only connects to canbus and 15, so it doesnt connect to the starter, starter is controlled by K40 from w202, allthough you have to wire the starter directly to the battery.
You have tp be creative on this. I use most of the w124 12v terminals and connect 12v wires according to the oem fuse block designation, so incase of a trouble i know where to look on the fuse box.
Dont just connect any 12v to any terminal, it is easier but one day when you run into trouble, you dont know where to find the loop.
Yes i do have the diagram, i will find it for you and post it here.
Please share picturea of the progress so i can better assist you.
Hi, I understood I have to modify the starter wire acc. to post #3 or did you mean the plus cable from battery to starter? Rest is pretty clear now.
Motor is out from my donor but we have snow fall today so I cannot make very much progress.
Btw wheel hubs from 97' SL are hard to find here in Germany too.
For the speedometer sensor I plan to put a trigger disc on the rear transmission flange, between tranny and flange. Should be more elegant than putting it to the prop shaft. Although it works great there but MB would not do so. Tranny crossmember is from w210, OF Gear Website says you can use any crossmember from w210 to fit the 722.6 tranny.
Last edited by Benzdriver91; 04-02-2022 at 06:28 AM.
Yes you have to move the battery to the trunk and connect the big cables directly to the starter.
i wish i still have my invoice for the SL500 wheel hub, i bought it new in fixparts.com
Its not so expensive, if im not wrong its $500 a pair brand new.
The knuckles is expensive. But you can modify it so it fits the r129 wheel hub.
I will search my email and hopefully i still keep se records.
Hi, ok it is clear now. I'm looking after these R129 hubs & knuckles, found one for the right side on ebay, complete knuckle assembly for~140 bucks. Late R129 hubs have 48 teeth instead of 96 like w124. I don't want to pay 500$ just for two hubs, it's a pitty that the market surrendering you is so restricted.
The weekend was pretty cold, but that's normal in G for this time. The very first days of april are always cold with snow falling. So I didn't do anything with my donor. Next days I wanna remove the wiring completely. I hope to find the wires from rear ABS sensors.
I also took a closer look to the NAG1 transmission, there is already a prepared sensor mounting position on the end of tail housing. It's possible to bore the cast flange but you have to move out all the inner tranny parts. It would be the most elegant way but it's too much effort at the moment. My tranny has just 225.000 km or 140.000 mls equivalent and I don't want to open it. So I will use the outside sensor with the four teeth welded on the driveshaft. In my mind there is an idea to use a lasered sheet metal ring with four latches angeled 90° and grasping over the rubber flex disc. This is closer to the transmission and no flexible part would be between sensor and ring. I have to make measurements first... and use my computer.
Last edited by Benzdriver91; 04-04-2022 at 06:40 AM.
Buy one set of knuckles with hub and try it on your car. It should fit perfectly.
Dont ever touch the tranny housing, that sensor houding thats located in the tranny rear housing is specificly used for G class. Why? Because g class has high and low transfer case. The EGS cannot read the wheel sensor because this high low feature therefore mercedes specificly make a few additional parts for G class purpose.
Inside that sensor is the parking lock wheel, eventhough you drill that hole and install the correct sensor, it wont read anything, you have the change the parking lock wheel to G class parts and it has 48 teeth, so it wont work on w124 electric speedometer. Also you will need special ballast for the sensor to work, so its super troublesome.
How do i know this? Because i just finished retrofitted my 1993 G300 with M113 engine and NAG transmission.
04-22-2019, 01:17 PM
