W205C43AMGCoupe

Absolutely disgusted right now. I have been running stage 1 software tune and was very happy with it for the last two months. Then of course I wanted more power, so I decided to install Weistec downpipes and resent my ECU to a vendor for stage 2. I receive back the ECU in about a week and install and the car won't start. I receive an error msg on dash which says "vehicle inoperable see owners manual." So i speak with the vendor and they say to unplug the battery for 15 min and re plug in. I do that and and still have same issue. Call back vendor, vendor tells me to charge battery fully. I used my jump charger to fully charge battery-car still wont start. Vendor tells me that sometimes there is power still in ECU if battery wasn't unplugged when ECU was originally removed and I should send it back to them to re program. Okay-so I send ECU back for reprogramming and get 24 hour turnaround it it (nice!) however, the car still wont start. I no longer have the error msg on dash and have full power and full battery but no start, no crank. I tried jump box, jumper cables with donor vehicle. I checked all fuses under hood, fuses in rear and fuses in passenger side and drivers side compartment and all are good. So I now know i'm screwed and had the car towed to the dealer (what else could i do?) I'm worrried about warranty issues if they see the aftermarket downpipes and ECU reprogramming. And I have no idea what is wrong with the car. Not placing blame on the vendor, but nothing was wrong with the car prior to sending the ECU out for reprogramming the second time. Does anyone have any ideas what could cause this on a brand new vehicle?

Plutoe

You may as well calm down,you will know the full story once they do a quick test with Xentry, however hope you have deep pockets as no dealer in their right mind would provide warranty and or good will for a tuned car!

Jimmy C43

Sorry for your dilemma, please report back regarding how the dealer is suggesting handling this

I want to tune my C43 but this is what scares me and the only thing holding me back

The AMR $2,000.00 tune is the way I'm going to go if I do it based on all the positive feedback on them in the tuning threads

Which vendor did you choose ??

W205C43AMGCoupe

Another shining example of how friendly and helpful members of these forums are. I've been members of other car forums where members were actually car enthusiasts who enjoyed modifying their vehicles, sharing ideas and helping each other out with issues. I obviously realize the dealer will diagnose the issue and that it will cost a pretty Penny. I still like to trouble shoot before hand what the issue could be.

cenzo86

There is a service mode the vehicle goes into if the car is powered off and the hood is open for a period of time. That might be what your tuner was referring to with the power to the ECU still.
I cannot seem to find exactly WTF I'm talking about right now as a reference point. I'll get back to you. Good luck.

Dthquazi

You seem to have diagnosed it yourself. You have shown cause and effect and even titled the thread with your own conclusion. Then you post it hoping for a miracle. Your problem has been experienced by few people and they seem to have had to do the exact thing you were told. Then you get snarky with them.

5ilver-5urfer

Out of curiousity, what happens if someone ships their ECU to a tuner and they end up misplacing it or it gets lost in the mailing process? Does MB void your warranties because you removed your ECU? Would diagnostics still pick up the fact that the car was tuned? Not saying you should fake losing your ECU if you've bricked it...just curious.

Mr. J

Occam's razor points to the tune. My shot in the dark guess is that the dealer will flash the ECU back to stock and all will be well.

If I were you I would already be processing a refund from the vendor of that tune. The complicated part is the catless downpipes. You can't run those with a stock flash without getting a CEL. Did you send the stock downpipes along with the car to the dealer shop? I suspect that the service manager is going to want to return everything to stock and reflash the ECU as the first step of troubleshooting this.

Worst case scenario is that the tuner bricked the ECU. If that is the case, you will be out the replacement cost of the new ECU.

What you aren't getting back are any fees for towing, reflash of the ECU, and labor to reset the car to stock. If they did brick it and you have to replace it, make sure to retain the bricked ECU. You'll probably need it if you are going to try to get refunded for the replacement.

If I were you, I would meet with the service manager and make it clear that you were never able to start the vehicle, let alone drive it with the reflashed ECU. It sounds like you have enough evidence to corroborate this, so be polite and patient and present the facts until he is satisfied and believes you. If you play it right you may be able to avoid getting "flagged" as a tuned car since you never actually ran the thing.

Hope it all works out.

unr1

I'm sure your salesman can answer this question :P

5ilver-5urfer

He probably can but I thought I'd give you a reason to spend more time on this forum to answer as well

unr1

<3

AMG_FVR

Would you mind sharing which vendor did you use?

AMG_FVR

Jimmy - I thought you weren't going with any modifications because of a lease?
We all get that mod bug in us as enthusiasts.

W205C43AMGCoupe

Hooked up Diagnostics reader today to OBDII: Got a whole bunch of codes. I suspect some of these codes may just be due to the ECU tune but unsure.

I cleared the codes but the ones related to the downpipes like 02 sensors wont go away. Still no start. MB looks at it tomorrow.

U0431
U0100
P0727
U0126
P1193
P1190
P0108
P0238
P24D8
P2505
P2401
p24BE
P0458

OBDII Test Shows:
02 SENSOR B1S1
02SENSORB1S2
02SENSORB2S1
02SENSORB2S2
CATALYST BANK 1
CATALYST BANK 2
VVT MON BANK1
VVT MON BANK2

EVAP 0.040
EVAP0.020
PURGE FLOW
02HEATER MONITOR B2S2
MISFIRE CYL 1,2,3,4,5,6

Mr. J

So are you going to return the exhaust to stock? You will have an easier time with MB if you do.

Did you install the downpipes and ECU at the same time? It would be good to isolate all your variables here.

getmercd

It sounds like maybe there is something unplugged on the car or maybe a mechanical issue. If the tune was causing it, you would have felt it with stage 1. It sounds like whatever vendor you are working with is being productive and diligent in trying to help solve the issue, which is nice to see. My advice is to check the ECU clips and make sure nothing is broken and everything is securely put together. Let us know when you find out what it is!

sean1.8t

Did you think about sending your ECU back to the vendor (for a 3rd time, I know) to have it flashed back to stock before you handed the car over to the dealer? Possibly putting the stock cats back in as well.

This is and has always been my plan if something like this was to happen. No way in hell that I'm going to give the dealer my malfunctioning car with all the evidence they need to void the warranty.

Jimmy C43

You're EXACTLY right about the "Tuning Bug" LOL

Now that I have been driving for a month (too much, 3,000 miles, gotta slow the clock down) I'm getting used to the car and the power

I have never had a car like this, so for me it was like a rocket ship the first few weeks but I'm getting used to it now

Yesterday, a guy with a V8 Mustang (relatively new, within a few years old) with a stick shift was next to me at a red light in an area I'm very familiar with, with a straight away in front for about 2 miles

He was revving his engine so I went with him when the light turned green

We were neck and neck up to probably 100+ miles an hour (I'd imagine, I did not look at the speedometer but was on the gas full throttle for about 10 seconds)

In these rare situations, a tune would be nice

AMG_FVR

3000 miles within the first month?? I hope you not using the car for Uber?
At least the car is broken in now and ready for a tune.

With a tune you should be able to spank that V8 Mustang next time you see him.

Be safe!

loungn14

Most times I have seen this error was due to the connectors not being properly seated or a bent pin when trying to connect the Ecu. Triple check the pins and connectors and reseat them making sure to feel the click when you seat them.

sterz85

any updates?

Mr. J

Make sure to do this at Cars and Coffee. If you wreck and run down a bunch of people everyone will just blame it on the Mustang anyway

W205C43AMGCoupe

Thank you all for the helpful suggestions and sorry for the delay. I've been traveling the last few days. First, I am intentionally not mentioning the tuning vendor because I don't want to place blame on anyone until the cause of the fault is determined. So far the vendor has been very diligent and helpful in working with me, even offering to pickup my vehicle and trailer it across state lines to their facility. I'm very pleased with their response in a day and age where so many are quick to place blame on others. The car has been with my mercedes tech who has been testing it and has isolated the issue to the ECU. Upon hooking the ECU up to starscan he found that the Driver Authorization (keycode) is essentially missing from the ECU, like its been erased. So the ECU is not recognizing the keys and this is something that cannot be programmed from MB unless its from corporate which will throw red flags because it looks like different keys are trying to be used to start a vehicle. Each ECU from MB comes from the factory programmed to two keys. Following codes were found and showed to me on print out:

Drive Authorization:
No. 500 Serial number of drive authorization system- "No value available"
Status of Drive Authorization - "NOT DEFINED"
No. 897 Drive Authorization Start Enable "Fault 53392/259"


I have resent the ECU and both keys to the vendor and they are going to work diligently to see what happened. Frustrating situation which is costing me $143 an hour for my tech to resolve, but happy to get such good customer service from the tuning vendor and hopeful all will be resolved shortly. This seems to be a very unusual issue that others haven't experienced. I'm sure its a one off issue.

W205C43AMGCoupe

Update** Sorry I've been away the past few days on business travel. This issue is now resolved. The ECU was flashed to stock and reflashed with stage 2 tune and running great. This seemed to be an unusual/ one off issue. Happy to have the car back up and running and now pulling very hard with stage 2 software paired with awe track exhaust and weistec catless downpipes. One piece of knowledge to share with forum members is that you can drive the vehicle with catless downpipes and no software tuning. As long as you "stay out of boost" as much as possible you can drive it for a few hundred miles until you can get software upgraded. You will get a CEL after approx 20 miles, but the car doesn't go into limp mode and the CEL can be removed with a OBDII reader. Thsi might be useful for those who are one the fence about stage 2 software first vs downpipes first. Thanks for all the help provided by forum members in diagnosing possible issues.

cenzo86

That's great news, glad to know you're back on the road. Did the dealer lean on you about the ECU software? Did they pull you into a backroom where the NSA questioned your citizenship and allegiance to America? Did they pull transcripts of your MBWorld account where you talk about bricking your car? Did they take your mother to a rendition site in Pakistan?

...or did they just reflash without asking you any questions and call you when your car was ready to be picked up?