ECU Bricked or Not Responding - 2014 Mercedes CLA 45 AMG

Hi Everyone,

I have a 2014 Mercedes CLA 45 AMG. I used the MVPI 3 and the TDN app. I thought it would be save to just read the vehicle ECU.
Apparently not. I just clicked on read the ECU and app copied some files, then I got a failure message. It would not allow me to cancel either.

Something happened and now my car will not start and error messages about parking break and 4matic not functioning and take it to a dealer. My car is now stuck in my garage. Yikes.

No previous issues with the car or ECU.

Anything I can do, besides remove the battery and let the ECU drain, because that did not work. Bosch ECU Med 17.2.2

Respectfully,
Aaron

I dont suppose its the original battery? My car sucks a lotta juice with the ignition on and I imagine it could do that with a weak batt. Either way Id check voltage and put a charge on it, or jump it and see what happens. When my batt is too low I get similar messages. It lists all the things wrong and to see the dealer.

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Originally Posted by chevota

I dont suppose its the original battery? My car sucks a lotta juice with the ignition on and I imagine it could do that with a weak batt. Either way Id check voltage and put a charge on it, or jump it and see what happens. When my batt is too low I get similar messages. It lists all the things wrong and to see the dealer.

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I will try that! Thank you for the suggestion.

To be safe, hook up a 20A battery maintainer while doing ECU stuff.

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Originally Posted by SolarSupremacy

To be safe, hook up a 20A battery maintainer while doing ECU stuff.

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Unfortunately, jumping it did not help.

Did you get the file from the cr or did it fail before you got it?
I ask because it does weird things while reading and writing. It'll say inoperative, do not shift gears and see dealer. I've never seen it claim some individual system was bad, which I only see when the batt is very low.
It also won't let you cancel, so per your post I can't really tell if you completed the read or not.
I forget how long it takes to do a read but I kinda remember it was 10 minutes on my car. Loading the patch took some time too, either of which can put a hurtin an a battery, both together is that much worse. If in the garage I suppose the headlights were on too? I turn mine off when doing this stuff.

So I'm doing a lot of assuming here, and based on all that assuming I'm guessing your voltage dropped too low during the read and the ECU faulted out. Maybe this caused the ECU to be stuck in read mode? I dunno, just a guess, but what I would do is another read to completion to be sure it's happy. Obviously use a charger this time, or jump it to keep the voltage up.
If that fails I'd say you need to create a ticket with HP.

I'm not sure what the min voltage the ECU needs to have for all this work properly, but I've loaded a tune with ~11.5V, maybe even less because I don't always check. Nobody will ever say that's ok, but I can fix a catastrophic failure so I'm not worried about it. The point is it worked, but at some point it will not. I don't know what it'll do at that point, but I'd imagine something like you're experiencing.

It failed before finishing the read. It took about 10 mins. I will have to check if I got the files. My obd2 port has power but is not responsive to any tools, including a cheap scanner.

My battery was over 12v after using TDN. I did try to jump it but no luck.

Well, I'd say jump it with a running car and download again. Assuming HP can see the car. If it doesn't see it then I suppose I'd start looking for blown fuses. Maybe unplug the batt overnight again?

If all fails and the ECU is hozed up from this then I suppose you could have the dealer reload the ECU. My local dealer said they would do it for one shop hour labor. I haven't read about anyone having to do this so I'm still leaning on you being able to fix it. Speaking of, I'd search for others with this or similar issues.
I was paranoid, since electronics fail all around me on a daily basis, so I backed up my ECU before I ever hooked HP up. Too late or you now, but if you're interested, I can explain how. Not too hard and costs ~$80.
Actually, I was one step paranoid above that and bought a spare ECU. The spare is what I do all my tuning on. Spare cost me $200.

I do have a backup of my ECU but since nothing connects to it through OBD2, not sure how I can re-load it. Do you know? I am going to buy another ECU too. That is a great idea! $200? Where did yoi buy?

That is super weird and I'd ask HP about it for sure.
You have a backup? I did mine via KESS but I had to open up the ECU and do it on the bench, not via OBD. There is one spot inside you have to apply 12V in order to get it to go into boot mode. My understanding is you need boot mode to acces it, or maybe it was just to access the secret part holding your security info. If using KESS/K-TAG I'd imagine it's the same story with yours, but apparently you did it via OBD so I'm not sure what kind of backup you have, or if it includes the security stuff. No security stuff, no worky.

I got my spare from a junkyard online: https://ebay.com/str/benzeenautoparts $170 + $20 ship + tax, which was in Jan '22.
Mine was from a '14 E63 but the main # (278 900 13 00) was the same as my '16 E550. I couldn't find one for my exact car, which I assume is because not many were made. Point being that if they don't have it listed for your car I'd search for another car with the same engine will work. Or use your ECU's part #. All the ads I saw, regardless of seller, were good about posting actual pix of the ECU with the sticker so you can see the part #.

Then I simply loaded my backup copy into the junkyard ecu and I was good to go. No virginizing or anything else required, other than power to that one spot to trigger boot mode.

Yes! I found a couple on Ebay testing and warranty and allow returns.. I would love to learn more about Kess so I can follow what you did.

Powergate 3+ (from VR Tuned) created the backup for me. It is a 19k file with a .usr file extension.

My backup files are 4k and no extension.

Link to zip file I have with KESS details and on how to do my ECU: https://tinyurl.com/bdrvsdr
Not sure about yours but here's the link to the KESS program: https://tinyurl.com/4wnupdrs
That way you can find your ECU and see how to wire it up.

Quote:

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Originally Posted by SolarSupremacy

To be safe, hook up a 20A battery maintainer while doing ECU stuff.

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Hope you mean to maintain your battery with a charger and not perform reading or writing with a charger connected. Every manufacturer I know and I was with GM for 25 years is a HUGE no to chargers OTHER THAN the approved Midtronics? PSC 550 Battery Maintainer (SPS Programming Support Tool (EL-49642)
to the vehicle or the GR8 (EL50313) in the power supply mode.
Will it fry your ECM/PCM/TCM/FPCM? Maybe, maybe not. I will ONLY use an off board or have a well charged AGM jumped to the factory battery. I will never use a regular charger. If you hook up an "O" scope it is clear as day the massive ripple you get with a standard charger much worse if you have a failing diode in that charger. Hooked it up to our GR8 and it is dead nutz solid line. No ripple of any kind.

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Originally Posted by i120bspeedy

Hi Everyone,

I have a 2014 Mercedes CLA 45 AMG. I used the MVPI 3 and the TDN app. I thought it would be save to just read the vehicle ECU.
Apparently not. I just clicked on read the ECU and app copied some files, then I got a failure message. It would not allow me to cancel either.

Something happened and now my car will not start and error messages about parking break and 4matic not functioning and take it to a dealer. My car is now stuck in my garage. Yikes.

No previous issues with the car or ECU.

Anything I can do, besides remove the battery and let the ECU drain, because that did not work. Bosch ECU Med 17.2.2

Respectfully,
Aaron

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Symptoms shows thats an ECU Brick, happens much with hptuners patching the file before read.

I can do it through teamviewer but you are going to need Tactrix Openport 2.0

Cloned KESS wont help you specially your boot is damaged.

Hi Everyone. Thanks for the help!

I took my car to the Mercedes Dealership. They ordered a new virgin ECU and programmed it for me for a low price of $1,500. So I have my car back with a working ECU.

Can I buy a used ECU (from the exact same car) and use KTAG and clone it with my working ECU from Mercedes that I just got?

I would love some help doing this if it is possible.

Chevota - your links above say expired. Can you reshare?

Stupid file share sites. I'll post it again when Im home. I would copy your new ecu file, via kess, to the old ecu. Didnt the dealer try reloading it? Was that a fail or was it more profitable to sell a new one? Either way I'd try it myself because I never trust anyone who stands to gain from their decision. I hear that crap all the time from vendors and contractors; "Cant be done". Then I do the easy/cheap cant be done way myself and send them a pix.
See previous post about cloning a junkyard ecu.

Apparently dealer does not have your fancy tools. Their Xentry system only allows to program a virgin ECU. I double checked with 3 dealers. Kess? Not the same as KTAG, right?

Oic. Ok, well you can with KESS. K-TAG is virtually the same thing, by the same people, but K-TAG is more for commercial and diesel while KESS is more for cars. Either works, apparently, but I chose KESS to better my odds of it including my car. My car still wasn't listed :( but the file in the link shows how I did it anyways.

https://tinyurl.com/yc2rux7r
Apparently these free file Xfer places are only good for a few days and a I think 5 downlaods? So hurry before others use it up! I can always make another so no worries

Link to KESS I bought: https://aliexpress.us/item/2251832170567616.html
Be sure you get the one with that black box in the pix below, which is to read our Tricore chip. I assume you have Tricore, but just get it to be sure
I also bought one of these: https://www.aliexpress.us/item/3256804449089021.html I didn't really need it in the end but it only $22 so wth.
If your ECU looks like mine then all the stuff in the instructions should apply. Mine is an MED 17.7.3. I wish I could say more about yours but I've only done my ECU. So keep that in mind when you wire it because yours may be different. I found my wiring in in the KESS program, and since it didn't have my car, only a generic MED17 selection, I "assume" all MED17 are the same? As for the boot pin, which is the one wire inside the ECU you need, the KESS program says to pull the board out of the ECU to access the boot pin on the other side, which I think is a really bad idea. It seems the board is epoxied in and I tried to remove mine but I bet I would've broke the board in my efforts. I found online that some people chose to drill a hole in the ECU to access that side, so clearly I wasn't the only one having trouble. So I researched for many (more) hours and found you can use a point on the visible side of the board. So of course I did that, and it's also how I made it so I can now access the boot pin without removing the cover on the ECU! All explained in the instructions with pictures and arrows :)

Attachment 127671

Thanks chevota - I got the KESS.rar file above downloaded. I am going to look it today.

I have Med17.7.2 so they are very close but might not be identical.
My backup (previously loved ECU) will be here Tuesday 1/24. My KTAG will be here on 1/29 and I also ordered the KESS just in case. That will be here 2/1.