Mercedes C Clas 2004 - Problems following battery change

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Sun 6 Mar 2016 20:03
Mercedes C Clas 2004 - Problems following battery change - T Bag

Hi John,

The RAC man came out recently and changed the battery in my 2004 Mercedes C class.

The battery works fine but for some reason the radio’s sort of wonky, drifting off the station – as though someone’s nicked the aerial and although I can physically lock the car with the metal bit inside the key fob, the button to lock/unlock and alarm it on the fob no longer works (I’ve had a new battery put in the fob at the Mercedes garage).

The Local Mercedes folk suggested that the two problems may be connected and want me to book it in so they can look at it but as a sort of “starter for ten” they’ll charge me around £150 to put it through the computer diagnostic machine.

What advice could you give?

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Sun 6 Mar 2016 20:23
Mercedes C Clas 2004 - Problems following battery change - elekie&a/c doctor

Before you splash out your £150,I would suggest the following.Open the boot,and on the left side you will see a rectangular access panel.Pull this out to check the fuses.It is possible that there is one blown,usually a 7.5 orange colour.Test this first .

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Sun 6 Mar 2016 20:40
Mercedes C Clas 2004 - Problems following battery change - RT

Electric windows and central locking often need re-syncronising after battery disconnection - and radio options may be lost as well.

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Mon 7 Mar 2016 07:34
Mercedes C Clas 2004 - Problems following battery change - BlakeAnderson

Replacement car batteries should be chosen by the battery's physical size. Take measurements of the length, width and height of the battery you are replacing and use those physical dimensions to determine which replacement battery to order. It is not necessary for the replacement battery to match the dimensions of your current battery exactly but they should be close in physical size. Take note of the terminal diameter, it should be either 10mm or 20mm, and whether the negative terminal is located on the right or left side.

Locate the replacement car battery by the part number. Typically, part numbers are typed on the top label of the battery. They consist of either numbers and letters or numbers only. Type the battery part number into search bar on right top corner of this page to find the proper replacement battery.

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Mon 7 Mar 2016 07:40
Mercedes C Clas 2004 - Problems following battery change - gordonbennet

Why oh why oh why do people, including mechanics and breakdown in this case, not connect a jump pack or other live feed to the leads when changing batteries (taking care to avoid accidental short circuits), makes life a whole lot simpler keeping everything electrical ticking over during the swap.

Obviously this applies to batteries being removed which are dying and not already fully discharged.

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Mon 7 Mar 2016 07:53
Mercedes C Clas 2004 - Problems following battery change - RT

Replacement car batteries should be chosen by the battery's physical size. Take measurements of the length, width and height of the battery you are replacing and use those physical dimensions to determine which replacement battery to order. It is not necessary for the replacement battery to match the dimensions of your current battery exactly but they should be close in physical size. Take note of the terminal diameter, it should be either 10mm or 20mm, and whether the negative terminal is located on the right or left side.

Locate the replacement car battery by the part number. Typically, part numbers are typed on the top label of the battery. They consist of either numbers and letters or numbers only. Type the battery part number into search bar on right top corner of this page to find the proper replacement battery.

Plagiarism - and incomplete as getting the correct type and CCA are more important than matching the physical characteristics

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Mon 7 Mar 2016 10:15
Mercedes C Clas 2004 - Problems following battery change - Wackyracer

I would try to resync the central locking and re tune the radio before splashing out for diagnostics.

have a read of the manual, it will usually have details of how to re sync the locking fobs.

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Wed 9 Mar 2016 06:36
Mercedes C Clas 2004 - Problems following battery change - BlakeAnderson

The passenger interior door handle went wonky and broke off recently. This is a well known defect for this particular model though. Not a big deal. Otherwise, this car is solid. Performs, rides, and responds like a sports car. I love it. Brilliant engineering. The maintenance is not cheap, but it's to be expected. It's a Mercedes. Anyone who is educated enough should know that if you constantly drive a vehicle like a race car, or push it to its highest capacity every time you get into it, more than likely something is going to fail, or need to be replaced sooner than later... It's common sense. I highly recommend this car to those who benevolently possess it.

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