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Easiest way to reset my ECU
Thread Starter
Senior Member
Joined: Dec 2009
Posts: 338
Likes: 1
From: Melbourne, Australia
2011 Ultima GTR
Easiest way to reset my ECU
Just wondering what the easiest / fastest way to reset my ECU is without losing all the other data / setting (clock etc).
I know I could pull a terminal off my battery, but is there an easier way?
You might be wondering why? I found a fresh reset ECU was very fun to drive. Very responsive, eventually the ECU always learns to be sluggish regardless how hard I drive (well, unless I do a mountain drive every day, but can't do that), just can't avoid driving slow most the of time in the city.
So yeah, thanks guys!
I know I could pull a terminal off my battery, but is there an easier way?
You might be wondering why? I found a fresh reset ECU was very fun to drive. Very responsive, eventually the ECU always learns to be sluggish regardless how hard I drive (well, unless I do a mountain drive every day, but can't do that), just can't avoid driving slow most the of time in the city.
So yeah, thanks guys!
Junior Member
Joined: Nov 2008
Posts: 71
Likes: 3
CL 55 AMG Kompressor
Hey fellow Aussie. The procedure to reset the ECU is as follows;
1. Turn the igniiton key to the "on" position which is just before you crank the engine to start.
2. Press the accelerator to the floor and hold for 5 seconds.
3. Then turn the key to the off position but do not remove the key, then release the accelerator.
4. Wait at least 2 minutes, the ECU is then reset.
5. ECU is now reset and you are ready to get new rear tyres.
The ECU rest procedure only erases the adaptive transmission and throttle settings. It does not erase any of the fuel, timing or other programming.
1. Turn the igniiton key to the "on" position which is just before you crank the engine to start.
2. Press the accelerator to the floor and hold for 5 seconds.
3. Then turn the key to the off position but do not remove the key, then release the accelerator.
4. Wait at least 2 minutes, the ECU is then reset.
5. ECU is now reset and you are ready to get new rear tyres.
The ECU rest procedure only erases the adaptive transmission and throttle settings. It does not erase any of the fuel, timing or other programming.
Thread Starter
Senior Member
Joined: Dec 2009
Posts: 338
Likes: 1
From: Melbourne, Australia
2011 Ultima GTR
AMG055 - Cheers mate, just tried it and it seems to have worked.
My measure for if it worked or not was what gear the transmission would stay in at 80. I remember last hard reset for my ECU it was sitting in 5th at 80 (S mode), but then through time it went to 6th. Just went for a hit and it was sitting in 5th, felt more peppy too.... so it seems it worked, THANKS!
Kaiba - An ECU reset wont wipe the flash, the tune will be written on the read-only ROM in the ECU, but there are adaptive throttle/transmission settings that the car "learns" through time. Unless you go WOT all day every day, chances are the car will start to become "lazy". At least, thats how I feel.
I plan to reset my ECU second day / weekly, that way the car will just always feel "fresh" to me.
Just my way of doing things really...
My measure for if it worked or not was what gear the transmission would stay in at 80. I remember last hard reset for my ECU it was sitting in 5th at 80 (S mode), but then through time it went to 6th. Just went for a hit and it was sitting in 5th, felt more peppy too.... so it seems it worked, THANKS!
Kaiba - An ECU reset wont wipe the flash, the tune will be written on the read-only ROM in the ECU, but there are adaptive throttle/transmission settings that the car "learns" through time. Unless you go WOT all day every day, chances are the car will start to become "lazy". At least, thats how I feel.
I plan to reset my ECU second day / weekly, that way the car will just always feel "fresh" to me.
Just my way of doing things really...
MBWorld Fanatic!
Joined: Aug 2009
Posts: 3,974
Likes: 2
From: NY
See Sig
Hey fellow Aussie. The procedure to reset the ECU is as follows;
1. Turn the igniiton key to the "on" position which is just before you crank the engine to start.
2. Press the accelerator to the floor and hold for 5 seconds.
3. Then turn the key to the off position but do not remove the key, then release the accelerator.
4. Wait at least 2 minutes, the ECU is then reset.
5. ECU is now reset and you are ready to get new rear tyres.
The ECU rest procedure only erases the adaptive transmission and throttle settings. It does not erase any of the fuel, timing or other programming.
1. Turn the igniiton key to the "on" position which is just before you crank the engine to start.
2. Press the accelerator to the floor and hold for 5 seconds.
3. Then turn the key to the off position but do not remove the key, then release the accelerator.
4. Wait at least 2 minutes, the ECU is then reset.
5. ECU is now reset and you are ready to get new rear tyres.
The ECU rest procedure only erases the adaptive transmission and throttle settings. It does not erase any of the fuel, timing or other programming.
MBWorld Fanatic!
Joined: Aug 2005
Posts: 2,207
Likes: 2
From: North Jersey
2012 CTS-V
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Senior Member
Joined: Jan 2009
Posts: 263
Likes: 1
C204, W209, W164
I'm pretty sure you're agreeing with me...but in any case, you cannot reset the ECU simply by doing what was said in the above steps; those steps reset the TCU. Whether or not the ECU actually creates a way in which the vehicle reacts to various things such as throttle input and shifting, is completely irrelevant to how the TCU is reset.
As far as I'm concerned.. the ECU controls air/fuel... not shifting.. after all, thats why a TCU is called what is..
As far as I'm concerned.. the ECU controls air/fuel... not shifting.. after all, thats why a TCU is called what is..
Senior Member
Joined: Jan 2009
Posts: 263
Likes: 1
C204, W209, W164
@Jguye; I believe that SPECIFIC process works only on W204's. I'd imagine that just as the way that you would enter dyno mode, the steps are specific to the model.
MBWorld Fanatic!
Joined: Aug 2009
Posts: 2,899
Likes: 93
C63 AMG
Alas, I tried this procedure twice tonight and failed to notice a difference under the same driving conditions/route/throttle. In "S" and AMG display mode I was in 4th/5th/6th at exactly the same points as before. I don't know what to say other than I tried it twice with identical results. 
Junior Member
Joined: May 2010
Posts: 47
Likes: 0
From: Perth, Western Australia
2010 C63 AMG (Marrano Tune and K&N airfilters)
I do this regularly as i drive predominantly in peak hr traffic during the week where i dont get over 60kmph. There is no doubt this works, i get wheelspin into second after doing this procedure which i dont get by the end of the week of driving in peak hr.
MBWorld Fanatic!
Joined: Aug 2005
Posts: 2,207
Likes: 2
From: North Jersey
2012 CTS-V
MBWorld Fanatic!
Joined: Aug 2009
Posts: 2,899
Likes: 93
C63 AMG
Hopefully some more of you out there will test this procedure out to see if it is the real deal. If so, it'll be a godsend and I will do it every few days. I'm going to ask my SA next week when I see him...I think he will know.
MBWorld Fanatic!
Joined: Feb 2009
Posts: 1,035
Likes: 0
From: Northern NJ
2009 C63
Was wondering about this actually.. On my ride to work usually i'm just cruising in M and throw it in 7 the whole time to save gas*, unless i'm feeling sexy (LOL 
), but otherwise just keeping to myself enjoying the ride. Would my tranny be adapting to this in a way that I wouldn't want (less aggressive)?
*if this is an urban legend, please let me know. could just be in my mind but i definitely noticed an increase in mpg so i've just kept doing it..
), but otherwise just keeping to myself enjoying the ride. Would my tranny be adapting to this in a way that I wouldn't want (less aggressive)?*if this is an urban legend, please let me know. could just be in my mind but i definitely noticed an increase in mpg so i've just kept doing it..
Last edited by drawde; Sep 11, 2010 at 01:15 AM.
MBWorld Fanatic!
Joined: Aug 2009
Posts: 2,899
Likes: 93
C63 AMG
Having tried this procedure yet again, I'm inclined to agree with what is said in post #294. I will get to the bottom of this with the service department at my store, hopefully with something definitive.
https://mbworld.org/forums/w211-amg/...-works-12.html
https://mbworld.org/forums/w211-amg/...-works-12.html
Member
Joined: Apr 2008
Posts: 94
Likes: 0
From: Los Angeles
C63
^ I agree. I have also tried it a few times and saw no change at all. As mentioned, I don't think this works on the 63 platforms. The only way I have read that actually work is disconnecting the batt terminal. I have not tried this myself yet though.
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Joined: Sep 2007
Posts: 7,136
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Corrolla
Having tried this procedure yet again, I'm inclined to agree with what is said in post #294. I will get to the bottom of this with the service department at my store, hopefully with something definitive.
https://mbworld.org/forums/w211-amg/...-works-12.html
https://mbworld.org/forums/w211-amg/...-works-12.html
Andy
