I was told by the MB Technician tht when you replace the battery you should follow this proceduer
1- MAKE SURE the GEAR LEVER is on P position
2- MAKE SURE the KEY is being remove from the ignition
3- Remove the NEGETIVE terminal FRIST then the POSITIVE
4- DON'T DELAY install the new battery
5- INSERT the key ignition turn ONN don't START THE ENGINE.Then RESET
THE RADIO CHANNEL and THE MEMORY SEATS.
6- START the engine.
Can anybody please confirm this proceduer cause i being reading alot of this topic and some even mention tht we have to reset the whole system all over again while the technician only mention the above proceduer only.
I usually call MB roadside assistance, they come out with a MB battery to wherever you are, install it, take the old one, and recode the radio and maybe windows. Dont go to the dealer they will charge labor, otherwise its about $100.
Your instructions are good, dont have anything on, especially the ignition, and do remove the key. The remove negative first, is the suggested proceedure, they typically come out with your radio code, but it would not hurt to have your card and then write it down if you dont.
Vehicle: E320, SLK320, MKV Jetta TDI, Mini Cooper S
Location: Arizona
Posts: 1,678
You will have to resyncronize the seats, sun roof and windows. I have never lost the memory settings for the seats or even the radio presets but you will have to put in the anti theft code to activate the stereo again. The ECU will be clear of any pending codes but will recalculate soon after you start driving again.
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If you're lazy like me you can clip a small battery, like a motorcycle or UPS battery to the jump points just before you disconnect the old battery (don't wait long because the little battery will drain fairly soon into the old battery)
Then take out the old, put in the new, disconnect the little battery -- no resets....
Replacing Battery For Model E200K Year 2001. 
Linear Mode
