after replacing the battery my e320 run poorly . I understand I may have to do a relearn procedure.
Does this vehicule require a relearn if the battery is disconnected? If so how is it done MN

 

What year is the car? Only '96 and later require a relearn. Even so, it shouldn't run "poorly" during this process. Maybe a slightly rough idle for a very few stop-n-go miles is all you should notice.

There are other adjustments being made but you need sensing equipment to tell what's going on. Your butt alone wouldn't notice the difference.

 

Which E320 chassis do you have ..
124/210?????
Did you jumper the car before changing battery?

if so,
Check the fuse on top of the OVP relay

 

1999 e320
By jumper you must mean temporaly install a 12v to prevent loosing the parameters in the computer during the replacement.
No I did not do that . Is it recommended ??

 

No
By jumper , I am asking if you had a dead battery before replacement and had jumpered the old one to start the car.
When this is done , it is common to blow the fuse on the OVP relay. But your vintage does not have an OVP.
That is why it is important to specify chassis when posting for diagnosis.

 

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