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So the ECU in my C32 caught fire as it was sitting idling after I pulled it out of the garage.. Caused a good bit of damage, but it definitely could have been worse. Surprisingly enough the fire retardant material surrounding the ecu worked very well and contained a lot of the damage to that area (even the wiring to the SAM stayed fully intact). Pulled the ECU and it's destroyed to the point it rattles and I can't read the label. At this point I'm fairly certain I need a new ECU, engine harness, front SAM, fuse box, and some of the wiring harnesses like to the windshield sprayer and to the brake fluid reservoir cap. That's straight forward enough but what I'm confused about is the software aspect as I'm getting a lot of conflicting information as I'm researching all this.

Say I get a new ECU from a parted out C32, how do I program it so the car will accept it?
Let's say I bought a knock off STAR DAS/Xentry setup, can I use that to flash it myself?
Now what if that ECU was not from a C32? Like imagine I got it from a CLK500 or a C240?
Would it be easier to just grab a ECU, EIS, steering lock, key, and cluster from a partout C32 and pop it all in at once than all this? (Would this even work..?)
Now imagine I grabbed a ECU, EIS, steering lock, cluster and key from a random other W203 chassis vehicle (C240, C320, C230), could I then reprogram all of this to work with my C32 using DAS? (Namely the ECU, the others all don't seem to be engine dependent but I guess might need to match the ECU?)
I haven't seen anything about having to program my SAM as long as the options match, worst case if they don't, those options just wont work, correct?

Sorry about all the questions, just really want to save this car and want to figure this out. I ended up buying a bunch of stuff already and want to get this straight before I throw more cash at it. Debating posting in the W203 main forum as well. Thanks in advance!
 

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1. Let's say I bought a knock off STAR DAS/Xentry setup, can I use that to flash it myself?
2. Now what if that ECU was not from a C32? Like imagine I got it from a CLK500 or a C240?
3. Would it be easier to just grab a ECU, EIS, steering lock, key, and cluster from a partout C32 and pop it all in at once than all this? (Would this even work..?)
4. Now imagine I grabbed a ECU, EIS, steering lock, cluster and key from a random other W203 chassis vehicle (C240, C320, C230), could I then reprogram all of this to work with my C32 using DAS? (Namely the ECU, the others all don't seem to be engine dependent but I guess might need to match the ECU?)
5. I haven't seen anything about having to program my SAM as long as the options match, worst case if they don't, those options just wont work, correct?
Considering that I do this stuff for a living, let me answer that.

1. Nope. SDS is incapable of reprogramming a used ECU to another vehicle, you'd need to buy other tools and do component level modification to virginize the ECU to a factory setting, then marry it to your car.

2. No, C32 has a supercharger and it'll have extra lines, extra mosfets, transistors that will support the extra harness for the extra sensors on the supercharger, so you're better off getting a C32 ECU

3. Yes, by far. It will work.

4. It will start the car, but again, since the random W203 bits won't have the supercharger extras, you'll get lots of odd codes and won't be able to version code it.

5. You can version code the front sam with the SDS, no problems

Your best bet is to either find someone local to you who can virginize a used C32 ECU and then you use the SDS to marry it to the car, or clone the original C32 ecu into used ECU....

....or buy complete TRP set from another C32.
 

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Discussion Starter #3
Considering that I do this stuff for a living, let me answer that.

1. Nope. SDS is incapable of reprogramming a used ECU to another vehicle, you'd need to buy other tools and do component level modification to virginize the ECU to a factory setting, then marry it to your car.

2. No, C32 has a supercharger and it'll have extra lines, extra mosfets, transistors that will support the extra harness for the extra sensors on the supercharger, so you're better off getting a C32 ECU

3. Yes, by far. It will work.

4. It will start the car, but again, since the random W203 bits won't have the supercharger extras, you'll get lots of odd codes and won't be able to version code it.

5. You can version code the front sam with the SDS, no problems

Your best bet is to either find someone local to you who can virginize a used C32 ECU and then you use the SDS to marry it to the car, or clone the original C32 ecu into used ECU....

....or buy complete TRP set from another C32.
Thank you for the informative response! Ok, I have decided to go with option 3. I am going to get these Theft Relevant Parts from a part out C32 about 4 hours from me.
Just to confirm, these parts are the ECU, EIS (Ignition Switch), Steering Wheel Lock, and Key, correct? I don't want to make that trip twice haha. I will be grabbing the engine harness from this car as well.
Do I need the cluster from it? I was planning on upgrading to a C55 AMG or facelift cluster later on anyways and my cluster is fine, if I don't need it at all I wasn't planning on purchasing one.
I do not necessarily need to code the SAM correct? Assuming I got one that matches somewhat well, I can deal with some non working functions like rain sensing wipers until I get around to coding them or finding a better matched SAM.
I don't think the ECU I have right now is in any condition to be cloned from unfortunately, literally scorched and the connectors melted.
 

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Discussion Starter #4
I thought I responded to this but I guess it didn't go through. Thank you for your very insightful and informative response! I think I will be going with option 3. Just to confirm, I will not need the instrument cluster, correct?
 

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Depends. If the mileage is too much out (like 20k) over the mileage stored in the EIS, the cluster may display dashes (-----) instead of mileage.

YMMV, obviously. Some people were able to put a used EIS with different mileage but kept the cluster mileage, others had to replace both as a set.
 

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Discussion Starter #6
Depends. If the mileage is too much out (like 20k) over the mileage stored in the EIS, the cluster may display dashes (-----) instead of mileage.

YMMV, obviously. Some people were able to put a used EIS with different mileage but kept the cluster mileage, others had to replace both as a set.
Hi again, so here's what I've done so far. I tried to find a matching TRP set but had no luck in doing so economically for my C32. What I ended up doing was buying an entire donor car. Now I thought this would make things simple but nope.

Here are the facts:
My car is a 2002 C32 AMG (the one I am repairing) I think built in 2001. It has a key that looks pretty nice and modern, chrome sides, separated buttons on the face, OEM key, backup metal key matches all the door and trunk locks. To my knowledge, everything inside the car electronics wise is original. How/why one of the previous owners got the modern key (I suppose maybe after losing their key?) is unknown to me. The car of course when it was built had to have had the normal older style key. My car by the way ran and drove flawlessly before the incident.
My donor car is a 2003 C32 AMG (bought it minus engine and trans and some things that were parted out) I think built in 2003. It has the older style black key, same type as one of my 2005 W211s (my other 2005 W211 has a chrome key slightly different from my C32's, all these different style keys make no sense to me). It ran before it was parted out, metal key matches all door and trunk locks. To my knowledge, everything inside this car is also original.

So, I pulled the ECU, Front SAM, Cluster, EIS, and ESL from my donor car expecting it to all pop right into my C32. Nope, literally everything is different inside??? ECU harness same, all plugs on front SAM are same, cluster plug is same. BUT, my original EIS had four small plugs, donor one only has three (one large flanked by two small). Original ESL had a three pin connector, donor one had a larger connector. None of the wire colors matched up at all. Steering column also had different wiring and plugs. Prior to disassembly of the cars everything had looked identical inside apart from a few different options. I am ridiculously confused why everything would be different, and have invested so much money into this project at this point. I refuse to give up.

So I went back to my donor car and dismantled it further. Took the dash harness out, and took the loom and wire wrap all off. Traced every wire related to the ESL and EIS and completely separated this from the rest of the harness to keep it all self contained. Ended up with a harness that had two connectors that go to Front SAM, one connector to light switch (idk why so much of the ignition related wiring is tied into the light switch), the connectors that go to ESL and EIS, one pair of green/white wires, two pairs of brown/red wires, one red/blue wire to instrument cluster connector, one blue/grey wire, one fuse holder, and a small bundle of grounds.

I detached the respective connectors from my C32, connected the two front sam connectors to front sam (one connector needed depinning and insertion of cigarette lighter wires and a pair of black/brown wires), plugged light switch into my new light switch connector, connected up my EIS and ESL, plugged green/white twisted pair into it's junction box, plugged the two pairs of brown red wires into their junction box, depinned and inserted red/blue wire into cluster connector, tapped blue/grey wire into matching bundle of blue/grey wires, installed fuse holder and fuse, and installed the ground at grounding post. I popped in my original 168k mile cluster.

Gave everything power, electronics all came on. Cluster showed SRS error which it didnt before and teleaid due to taking off center console. Mileage flashed between dashed lines and 168k, showed correct outside temperature, *fuel level showed correct fuel level 1/4 tank* *Using black donor car key, car unlocked and locked*. Put black key in EIS, ESL unlocked. Car did not start. Windows don't work, seats don't move, steering wheel buttons do nothing to cluster display. It's as if the car doesn't know it's in run mode?? Like as if accessory power doesn't even come on.

Tried installing 190k mile donor car cluster in, still no start, showed correct outside temperature, *fuel level no longer shows anything*, mileage stops flashing dashed lines stays at 190k miles. Frustrated, reverted everything I did back to original wiring (kept it all intact) including front sam, etc, put back old eis and esl. Chrome key no longer unlocks or locks car, can't remember if it did before I did all the wiring stuff. Left the donor car ECU and SAM since mine are toast (did at one point put back my original front SAM just to see what would happen, no difference at all bad or good) Still no start ofc, but it acts just like it does with the new wiring and new EIS, ESL, key. As if it makes no difference that I put all that in.

Connected up all my new stuff back in again being sure to disconnect old things (except left green pairs and brown pairs as I can't trace them without dismantling my dash, BUT I did just try to remove all brown pairs and green pairs from junction box just because, and attempted start, no difference at all??? Even though it's CAN wires so it should have made a difference, but nada, no good or bad difference), now black key does not lock/unlock the car anymore, outside temp on cluster shows 185 degrees instead of correct temp, mileage of 190k not steady anymore flashes now like 160k cluster did with dashed lines. Attempting to start does nothing. Again, as if it doesn't even know its in run mode? As if its only in key position 1 not start. With shifter lock cable hooked up to (either old or new) EIS, key in position 2, foot on brake, shifter does not unlock, have to use the emergency release. Steering buttons still don't work. Currently at a loss for what to even try next.

I'm just mad as to why the hell the EIS and ESL connectors are different in the first place, and no one online seems to have a single clue as to why. On eBay I see some sellers advertising EIS's for 2003+ W203 that match my donor car's connectors so at least they seem to know there's a difference but I see no other mention at all anywhere online that the dash harness for an early w203 is completely different to a later w203 (despite both being prefacelift) or why this is the case. I also can't even find any EIS like mine with four connectors and a chrome modern key (my 2002 C32 key looks exactly like a 2015 CLA key if you want to look it up, 2003 C32 key looks like every other early W203 black key).

If you were in my situation what would you do? My current thoughts floating around in my head are that I should find a junkyard W203 that has the same exact dash harness as my donor W203, grab the harness and related steering column electronics and such from that, and gut my C32 and throw that harness in there. I am wondering if somehow my original *and* my donor front SAM's are toast or got ruined in this process somewhere hence 185 degrees and no locks etc. So I'll grab one of those too to see what happens (want car to start first, option coding can come later) Then, take my donor C32 modules and plug *everything* in from there to my C32 with that nice fresh harness. This seems like a last resort solution though (assuming it even works :( ) and I would be open to suggestions for easier things to try first. I wish I had STAR Diagnostics, don't know for sure but I feel like it'd help point me somewhere. I still need to change my engine harness after all this (mine is technically intact but burnt wire insulation and such in small places, need car to at least try to start before I go there though, I have all wires isolated and insulated well so nothing shorts there), at least that should be the same between the cars.

I know I wrote a lot but I tried to be as descriptive as possible, read through it, you at least might find some entertainment value, but any suggestions would be extremely helpful!
 

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Discussion Starter #8
I don't know how you could fix this without a Xentry Star SDS system you may want to consider getting on.
Paul
I'd love to if I could obtain one for a more reasonable price tbh. But nonetheless I'm really not trying to program anything rather just transplant all the relevant parts to my car from (what I thought) was an identical car.
 

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An SDS setup is only $600; given what you're trying to do, how's that a problem? Besides, since you're clearly a DIY-type (like me), you'll find SDS quite valuable for maintaining this car as time goes on. Best $600 that I've spent if I'm going to own this era of Mercedes-Benz.
 

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An SDS setup is only $600; given what you're trying to do, how's that a problem? Besides, since you're clearly a DIY-type (like me), you'll find SDS quite valuable for maintaining this car as time goes on. Best $600 that I've spent if I'm going to own this era of Mercedes-Benz.
Yes, I definitely know it's worth it and would be invaluable to me working on these cars, I probably will buy a used setup soon but I'm actually a broke college student is all. I actually don't have "a lot" of money into all this here right now as I've been doing all of this by myself extremely economically (junkyard flat rate pricing parts that I'm pulling myself, parts car was super cheap that I went and drove to get myself several states over, etc).
 

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I'd love to if I could obtain one for a more reasonable price tbh. But nonetheless I'm really not trying to program anything rather just transplant all the relevant parts to my car from (what I thought) was an identical car.
If you don't need pre 2002 vehicles and have a laptop you can use a so called passthru device.
Cost is around $300 I send you pm with detail later.

Sent from my SAMSUNG-SM-G870A using Tapatalk
 

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W203 as of 03 were a mixed bag, they used EIS from a W211, same with ESL. It literally depends on what options the car came in with, as certain 203 will be optioned with a different type EIS/ESL because of a certain option.

This was before the front SAMs could actually have more options beyond certain codes.

(except left green pairs and brown pairs as I can't trace them without dismantling my dash, BUT I did just try to remove all brown pairs and green pairs from junction box just because, and attempted start, no difference at all??? Even though it's CAN wires so it should have made a difference, but nada, no good or bad difference), now black key does not lock/unlock the car anymore, outside temp on cluster shows 185 degrees instead of correct temp, mileage of 190k not steady anymore flashes now like 160k cluster did with dashed lines.
Those green and brown wires are absolutely critical. They are the CANBUS wires....how do you think the EIS communicates with the ECU to start the car? It's through the green CANBUS wires. Brown CANBUS is the powertrain system, i think. If those are disconnected, no communication, no start.
 

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W203 as of 03 were a mixed bag, they used EIS from a W211, same with ESL. It literally depends on what options the car came in with, as certain 203 will be optioned with a different type EIS/ESL because of a certain option.

This was before the front SAMs could actually have more options beyond certain codes.



Those green and brown wires are absolutely critical. They are the CANBUS wires....how do you think the EIS communicates with the ECU to start the car? It's through the green CANBUS wires. Brown CANBUS is the powertrain system, i think. If those are disconnected, no communication, no start.
Ok so as far as the CANBUS wiring, I have checked and replaced literally everything up front dash wise. So instead of the hacked together initial harness I tried (which honestly should have worked as I did it correctly in my opinion). I then replaced the dash harness with one out of a 2005 W203. I didn't think it would work anyways as the wiring ended up being rather different (CAN bus wiring completely different, but the EIS and ESL harness was correct which is why I attempted it). No difference with anything.

Next I pulled another harness from a 2003 W203. This ended up being identical to my donor C32's and what I am certain needs to work. So I installed that and... nothing. Still does the same exact stuff. I pulled the front SAM's from the 2005 and 2003 and tried both. One peculiar thing of note was that when I first installed the 2005 SAM when i tried the remote the door locks worked. Then as soon as I tried the key in the EIS, locks no longer worked anymore. Also currently neither of my instrument clusters show the shifter position. The cluster also does not turn on until the second key click (it should turn on at the first click). Something *may* be corrupting the front SAM's. I also checked the power distribution block fusible links and all visible ground points I could see under hood and with dash and front carpets off.

I tried using Xentry to help a bit but I don't have a good enough cable quite yet, either way I don't think it's going to be much help at this stage as the car sees none of the control units (my setup for Xentry works on my other cars). I have attached a picture that illustrates this. Doing a CAN test isn't even possible as the car doesn't even see the EIS. Bummer.

SO, I think it *is* a CAN issue of some sort and I have to have a short to ground somewhere? What does this mean? Going to have to do what I was dreading... I think I'm going to pull the entire interior to check all wiring in the car, will go ahead and replace rear SAM too (hadn't replaced it at all yet).

Before that I'm planning to put all my wiring and modules back into my donor car and see what happens just to test and see if I have a solid basis to work with even. As long as all the modules can interact with each other I figure the fault can't lie within the stuff I've already checked.
 

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Status update. It totally was the can bus wiring. Ripped the entire interior out of the car and transplanted the entire wiring harness from a 2003 into it. Decided to do this after putting all of the modules into my parts car and them all working just fine after. Looking through the old wiring it had a ton of shorted wiring throughout including several can bus pairs, making communication impossible. After this transplant and replacing all blown fuses again I finally got the car to start right up!

I also had to replace the shifter assembly, clock spring, turn signal/cruise/wiper stalk assembly, and steering wheel airbag due to incompatibility with the 2003 harness (I'm honestly shocked as to how literally everything between the 2002 and 2003 cars ended up being *completely* different despite being the same damn car).

Unfortunately it was running like garbage (high idle, any throttle would cause the car to start revving up and down) which I attributed to the damaged engine wiring harness, so I pulled the supercharger and everything off the motor and pulled all of the wiring. Currently in the process of putting all of that back together, hopefully it runs well again after this.

I still need to convert the fuel system to MAPS due to the new cluster being coded differently (doesn't show fuel level unless I use the old cluster), which will entail pulling my fuel pump and replacing it with a 2003+ unit, running new wiring to the rear SAM, and then I'm just going to replace the rear SAM too with a newer unit to save the hassle of coding that.

Then I will be going through all the functions of the car and making sure it all works perfectly again and finally reassemble it all.
 

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Well, I'm honestly impressed you got this far, but at this point you might as well transplant the whole donor car into your current car.

From your earlier post #1 case, it would've been easier to find a used M112K ECU from somewhere else, have someone virginize it and then you'd marry it to the car with your SDS.

But wow, that much work....I do have to commend you. I certainly wouldn't have done that much work to begin with.
 

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Yes, that totally would have been easier if the rest of the car were intact but I'm glad I got the donor car due to all of the rest of the fire damage lol (would have to source every single thing from various different cars)

And basically that's the plan I think, just so everything works in harmony.

Currently I'm dealing with a few really annoying issues, I have zero braking power despite replacing the brake fluid reservoir and filling it, and pressing the brake doesn't unlock the shifter. Thinking I'm going to replace the pressure switches and master cylinder and after that bleed the brakes and seeing if there is a difference.

The bigger issue is that the car doesn't idle. Starts right up, revs strongly, but as soon as I try and let it idle, it starts misfiring and stumbling and then after a bit of that it starts revving up and down and loses all throttle pedal response. It's a brand new throttle body (I still have the old one though) and a brand new throttle pedal (I have three in total now) plus I just replaced the whole engine harness (I thought this would fix it). Now I'm wondering if I'm looking at this completely wrong in regards to this issue and I have a vacuum leak somewhere. Ordered new manifold gaskets for where the supercharger mounts up, and considering doing all the injector seals. Any other suggestions?
 

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Do a smoke check for vacuum leaks first. Failure to maintain idle is a very good sign of a massive vacuum leak.
 

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Do a smoke check for vacuum leaks first. Failure to maintain idle is a very good sign of a massive vacuum leak.
Absolutely, I wish I checked it all over first tbh, before ordering the manifold gasket I was hmm let's try spraying some starting fluid around the motor, right away the engine sputtered and the idle changed and everything so it's definitely got some kind of leak somewhere.
 
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