Hubi

Hi

FIRST OF ALL THIS IS FOR MY OTHER MB - A170 CDI

I put it in here because we dont have an A class section and I am usually here since I am the owner of the E class.....
anyways, this can be a problem in every MB with AT

In my mom's A170 CDI I found a problem with an Automatic Transmission.

When accelerating - everything is fine - smooth and clear, but when braking or slowing down, I can really feel downshifting. The transmission doesn't change the gear clearly and smoothly. I called one guy and he said that it can be a transmission bushing under it or I need to add the oil....do you have any ideas what is wrong?
Also, I found that when i put on R and release brake, sometimes there is a little jerk.....

thanks
HUBI

Polar Bear

I would recommend taking it to the dealer and have them clear the Transmission Adaptations in SDS. This allows the computer to relearn the tolerances and compensate for wear in the transmission to allow smooth upshifts and downshifts.

When they do this, you will still have rough downshift until the computer learns the pressures and engagement speeds of the transmission, and it will adapt accordingly. You can drive using the MB pattern to speed up the adaptation, or driving for a day or two with normal driving typically will hit the parameters and allow it to learn.

Hubi

Can the Transmission Adaptations be cleared by pressing the gas pedal? I read that pushing it and holding for an about 5 seconds allows us to clear it...

??

Hubi

petep86

where did u read that at?

Hubi

here at the forum:

(...) but here is the procedure:

1. Turn the ignition key to the on (not start) position.
2. Press the gas pedal to the floor and hold for five seconds.
3. Turn the key to the "off" position (don't remove the key), then release the gas pedal.
4. Wait at least two minutes for ECU to reset..

This will reset the ECU and the adaptive gearbox. You will notice and different shift pattern.

Polar Bear

Short answer is I don't know. I have read that many places, and have tried it a few times on my CDI but honestly did not notice a difference doing it. It may be more noticeable on higher performance engines like the E55, but on the CDI I honestly could not tell any difference. I have never seen this procedure documented in any Mercedes literature either. I would really like to see the source of it. People with E55s and even other E-classes say it works.

The SDS method I know works, but you are welcome to try the accelerator thing to see if it makes a difference.

The SDS method resets all of the speeds in which the transmission engages each gear, addressing the problems you are seeing. The other method you posted I think only addresses the shift points, and not the other parameters.

Hubi

I will check it out on my E320 when I get it (is coming from US to Europe) and let you know. And with this A class, probably i have nothing more that contact MB service and ask for a reset.....i am sure they will reset my walet to in europe...