- Mercedes-Benz C-Class: How to Jump Start Mercedes-Benz (and W205)
Step by step instructions for do-it-yourself repairs
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List of faults that occur after disconnecting battery...
left lights and the battery is dead. what's the mfg's recommended procedure on removing and replacing the battery? I've heard a lot of horror stories that have me very tenative to tackle the task myself. I'm tempted to let her roll down a hill and pop the clutch. I've heard the rear fusebox and possibly the the front fusebox can be killed when the new battery is hooked up. Can you help me with the recommended procedure?
Everyone who keeps their car long enough will eventually have to disconnect an old battery to replace it with a new one. Given the emergency nature of dead batteries when you least expect it, a dealer with expertise may not always be handy, either. So, it would probably help to identify what can happen, and the fixes you have found to correct them.
If we get enough responses to these, I will make this a sticky thread so all of us can find it in the future. So please share your experiences here. Thanks.
I always disconnect the negative first though, as you should for any car. Not sure how this would affect the rear-sam, but for $320, I'd say it's something you don't want to chance!
the only problems was just the moon roof resyncing. any help
ESP not available, but this one came off a few minutes before
Display Faulty, the gas gage doesn’t work
The trunk won’t open
And the fuel filler flap doesn’t lock.
Some people think that maybe problems with the computer and need to be reset, y really don’t know what to do, and I also don’t have a MB dealer near my city, I appreciate any help if any of you know about this problem.
The Best of Mercedes & AMG
All in all...$97 bucks to change the battery and to make sure everythign is running good.
I have exactly the same problem. If I leave the car idle for more than 3 days the battery runs off, while the fan is always running...

This is a W203 C320, there HAS to be a fairly simple way to swap a battery
This is a W203 C320, there HAS to be a fairly simple way to swap a battery

But, there was a problem getting the bracket off. I didn't have a 13 inch socket wrench EXTENDER to get down in the bay, on the side of this massive battery to unscrew the one bracket screw. so, I call roadside, they came, pulled the battery, put in the new one, took the old one, no charge. I tipped him though, seemed happy enough.
Nice to know, that they will come for the LIFETIME of the vehicle and jump, or replace and charged for the battery, totally free.
No issues what so ever other than: my stations on my radio had to be re-programmed and the trip computer was reset back to 0 for both current and history.
I don't know why people not only choose not to read the manual, but worst yet, come up with uneducated dangerous ideas.
I have disconnected the battery on my E320 and C230 several times. when In needed to replace them or doing works that I wanted to make sure no pwer source was present.
Comon sense prevails, of course make sure the ignition key is not on whe you are connecting/disconnecting the battery, as you will cause transients to go to all powered components when connecting and disconnecing it.
Resetting the things after th battery is reconnected is actually fun, like teaching a robot to walk. It is not a failure, but a way to manually teach the electronics what the full range of operation of things are. This is done mostly for safety, I am sure.
In regards to placing a battery in parallel (in case you think re-teaching the car is not fun), definetely again, if you have no clue what you are doing then you should never be doing it. If you place a 9 V or lower voltage battey in parallel with your car battery and the car battery voltage is higher you will cause a surge current into the battery you are connecting in parallel and may overheat / damage it in a short few sec and even hurt yourself or do some damage, unless proper isolation diodes are placed in series with it . (If you don't know what it is don't ask , you should not be doing this job anyways).
So in summary, contrary to some theories, the cars electronics are not designed to self desintegrate if common sense and some manual reading is done, prior to connecting/disconnecting the battery.
BTW, I never had any ESP alarm after connecting a battery back.
Incidentally if you close the trunk after taking out the battery, be aware that you will need the metalic key to open it again by turning the cilinder a quarter turn counter-clockwise (CCW or left in lay terms) and then push the cilinder in.
Last edited by guanabara; Nov 25, 2007 at 11:25 PM.
They will come to your house jump the car up, or even replace the battery at the normal retail price with no installation charge at all. No other car company I know would do that. So go on enjoy the day,.
They will come to your house jump the car up, or even replace the battery at the normal retail price with no installation charge at all. No other car company I know would do that. So go on enjoy the day,.
well this is my first problem with the battery.
my batt totally died so i am thinking of what i should do. will i be able to jump start it without any faults?
because last time i my dads s-class was jump started then the seat buttons was faulty. i called a dealer today asking whether i will get any fault codes if i jump started but they said no. i now i'm

the reason i can use any of the chargers are because my car is parked in an apartment garage and the garage doesn't have any outlets so there is no way for me to use a charger.
Last edited by wuufer001; Feb 4, 2008 at 01:46 PM.

anyways, just go buy a battery from an auto parts store and DIY (its either a group 47 or 49). very simple procedure. don't be prude just because it's a "MB"!


well this is my first problem with the battery.
my batt totally died so i am thinking of what i should do. will i be able to jump start it without any faults?
because last time i my dads s-class was jump started then the seat buttons was faulty. i called a dealer today asking whether i will get any fault codes if i jump started but they said no. i now i'm

the reason i can use any of the chargers are because my car is parked in an apartment garage and the garage doesn't have any outlets so there is no way for me to use a charger.









