So my OEM battery finally decided it had enough, quite impressive considering it is ~8 years old and has never been touched. I started experiencing slow morning starts this past weekend, would start fine unless the car sat for 8+ hours. Figured I could limp it along until this weekend but yesterday I go to leave for work and it BARELY got the car started, I knew if I let it sit all day at work I would be stuck and trying to find a jump after work.

My preferred dealer wanted a whopping $370+tax (figure $390) for this task. There is a point when I just cannot justify the convenience of not having to touch it myself so I decided to tackle this myself and save myself $200.

I hauled myself up to the dealer parts department and got a pretty fair price on the battery ($169+tax - ~$178 including tax), bought a battery terminal brush from Autozone ($4.75) and came home to get to work. It was a comedy of errors to say the least, first I was missing the 10mm box wrench I needed for the terminal nuts so went and spent ~$8 for a replacement box wrench, come back home and start working but realize I can't find my ratchet extension to reach down to the battery hold down bracket, back to Ace hardware for a $7 extension. Good to rock on! Only other hiccup I ran into is I disconnected the battery and the new battery was in the closed trunk. I was able to use the physical key to open up the trunk thankfully after some fiddling with the remote fob.

Process was pretty straight forward and easy, the hardest parts were maneuvering the HVAC plenum back in place and lifting that heavy SOB out of the car. I ended up not needing the battery brush or even the baking soda I bought as there was ZERO corrosion on the terminals and the battery tray was immaculate.

Nothing in my car needed re-programming, I was already planning on having to resync the windows and sunroof but they all worked just fine after the replacement and I had the battery out and disconnected a good 15 minutes. All is well now and she starts just fine now!

So dealer cost (tax estimated) - ~$390
My cost - ~$195

Saving $195 and lets say 1.5 hours of time had I the tools I needed, this consists of trip to dealer to pick up the battery and the trip to go recycle the old battery. Definitely worth the trouble and headache I had to endure.

 

Battery swaps on the 204 are very simple, as you say the worst part is lifting the heavy battery out of the hole it sits in. The air intake box that has to be moved is prone to having the clips break off, if you're not careful.

There's no reason any person capable of physically lifting the battery out couldn't replace it themselves. Not much to it.

 

Autozone installed the battery I bought from them for free back when I had my W203. It sounds like the W204 is a bit more complex, though. My dealer (RBM of Atlanta) wants $310 to replace the battery and no way in hell am I paying that.

 

It's not that it is complex, you just have to pull the HVAC plenum which also doubles as a battery cover and the cubby the battery sits in makes it not the easiest to lift that heavy SOB out. I was looking aftermarket at first but surprisingly the non-OEM batteries (Duracell) were just as expensive and in some cases more expensive than the MB battery. The original in my car lasted almost 8 years and there was ZERO corrosion to be found so I figure I would stick with original.

$310 is not too terribly bad, yeah they are charging you 1 hour of labor minimum but when you factor in the full service car wash you are paying maybe $100 for the convenience of having to not touch it. My sales guy at Malone's in Marietta recommended RBM but it is just too much of a haul for me.....MB of Buckhead is only 15 minutes away, have not had any issues with them and I can usually get a loaner on my service visits.

 

Autozone batteries are ok (I've only bought their AGM's) and installation on the W204 is easy enough to do yourself. No special tools and definitely not a dealer job.

Physically identical :



Pulls straight out and lots of room to work :



Drops right in :

 

Did you get a price quote on battery replacement from Malone's service department by any chance? I think we've talked about them in another thread before, but they are fantastic.

 

*every other car*
disconnect wires
remove and replace battery, recconect
*mercedes*
OK STEP ONE REMOF ZE AIR INSTEAK

 

10 minute job when I did it. I had the tools. Literally flip a few tabs, remove plastic box. Undo battery terminals, swap, fasten terminals, put back box, clamp tabs back. Done. 20 min drive round trip to dealer, no problem lol no thanks on paying $200 for simple work.

 

I didn't this go around - it was kind of a urgent replacement I needed as required me take a vacation day from work to handle and I just wanted to get it done.

 

Ok this is freakin hilarious......yet so true!