WhiteKnight16

So I just had my ECU flashed a couple of months ago and when I got it back I had major issues with the distronic drive/cruise control. Every time I am going over 60 mph and turn on the distronic, my car loses complete power. I have to basically roll off the highway and turn the car off and then back on to regain power. The ECU flash company (reputable) says that this is a common problem with a few C63s and believe that a software update/fix is needed from MB. What do you guys think?


They have tested my same flash on their cars and haven't had any problems. Should I take the car to the dealer and have them take a look/update/fix the distronic software? I was told that the flash most likely isn't the problem as their cars do not fail like mine and that the dealer may need to fix it. They also said that MB will not need to reset the ECU and so the flash will not be reset/messed with but only the distronic software needs to be updated.




Hopefully someone on here has had the same problem or know what is going on? Here are the signs I get every time the car fails and loses complete power:

dforman15

If you take the car to the dealership for repair and they see that you have flashed the ECU, more than likely they will place blame on you and say the work is not covered under your warranty.

WhiteKnight16

To my understanding, the tune company told me that it is unlikely they will even detect that there was a flash unless I tell them that the car has been flashed. Also, this is a distronic issue rather than a ECU issue, so they might not even look at the ECU?


Do you know if my warranty would be void or just that claim if they did deny fixing it for me due to the flash?


Thanks

Gungaslow

Use the lemon law to return the car

dforman15

I think people tend to underestimate the dealerships. I know its a distronic issue but everything on the cars runs through the ECU. It's the main computer on the car that controls everything. If they know you have tuned your car I think it up to them at that point if they want to void the warranty all together or just deny this claim. Next time you bring the car in for something else, if they know your car has a tune they can blame everyone on that if they want.


I had a friend who had an M3 with a JB4 tune or something (not that familiar with it) and they voided his whole warranty. Parked his car on the lot and told him to come pick it up for pay for the work. Its always a risk. Just my opinion

NSAMG

Well holy ****. I just had the DPS and ECU flashed and installed yesterday,and guess what same thing happened to me on the way home yesterday, and a couple times today. So no cruise control to get home. Once home I emailed the supplier and he told me the same thing that it is a problem with the Distronic issue. But I did not get the Distronic option.

dforman15

doesn't sound like a distronic issue

vaelin

Sounds like the tune screwed up Distronic. Because if it was working before the flash..

NSAMG

Unless I am miss understanding the Distronic option. It is the electronic feature that applies the brakes if you get to close to the object in front of you. But you can have cruise control without this option. If this is correct, then I do not have the Distronic option. Unless its a coincidence, I never had a problem with my cruise control until yesterday. less then one hour after having the flashed ecu installed

AlexZTuned

Mercedes will immediately void your ECU warranty if it's been flashed to their knowledge. So any issues caused by a faulty ECU (as some have already mentioned, modern ECU's control much more than just the engine), will not be covered under warranty. This Distronic problem seems directly correlated to people that have flash tunes, so you can bet that Mercedes will not cover this if they find out you've tampered with the ECU.

It's a major pain, but your best bet is to reflash your ECU back to stock and hope they do not dig into the data and see any traces of the tune (engine parameter outside of stock). When the problem has been resolved, get your ECU reflashed back and hope it doesn't cause another issue.

This platform desperately needs OBD-II flashing or a reliable warrantied piggyback (read: Dinan).

vaelin

Distronic is adaptive cruise control. Once enabled, you could go from 70mph traffic to nearly dead stop in traffic and it will start moving, maintaining a safe distance from the vehicle in front of you.

Coupled with Lane Keep Assist, it's basically a limited form of semi-autonomous autopilot.

I've driven 40+ miles, in bumper to bumper traffic going home, with it.

vaelin

Heh.. piggyback though only goes so far; won't solve CEL from emissions-related mods that a bench/OBDII flash would. But the PITA of extracting the ECU for bench flash, coupled with this sketchy feedback of losing Distronic..

NSAMG

Ok thanks that's what I thought. I do not have Distronic but still have this issue.

jkob5

I too have this issue after getting a eurocharged tune. Those with this issue, what company tune did you get? It's pretty annoying. I have decided for now to just let it be. Distronic still works at low speeds (traffic jams), but it is painful hot to have any sort of cruise control on long drives as you can't separate distronic from cruise control. I got the same reply you did but don't want to have my car title 8'd

NSAMG

I wish I new of this issue last week. I am headed to Montreal Thursday for the F1. Once I get back I will send the ecu back to get reflashed to stock. then reinstall and see what happens PITA.

jkob5

whose flash do you have? I have only heard of EC being affected but I bet it's all of 'em

NSAMG

Does the Distronic , control the electronic rear axle differential lock ?

WhiteKnight16

I just heard back from the dealer. I was told that they are ordering a new Distronic module from Germany. I asked if that meant a whole new ECU and the service rep didn't think so. Do you guys agree?

vaelin

That's the front star radar unit.. no/

jkob5

This will probably fix your distronic but clearly it's a software issue not a hardware issue. I bet however when they program the new one to your car, it will work fine.

AlexZTuned

More than likely when they reprogram, they will flash the car with an update as well which will wipe out the tune. If this happens, the ECU will need to be removed and reflashed with the tune... hopefully that doesn't cause the Distronic issue again as that seems to be the culprit.

WhiteKnight16

Is there a sure way of telling if the flash has been reset other than dyno?

jkob5

if you have catless downpipes the CEL will come on. You want that to happen when you have the car and not the dealer.

NSAMG

I have had the CEL light on since having this issue. How do I remove it.

WhiteKnight16

I don't have any upgraded downpipes, just stock car with the ECU flash.


Every time my car went through this problem, the check engine light comes on and stays for about 50 miles or so. It then resets and goes away. I think another way of getting rid of the sign is by just normal use of car - turning it off and on a few times