secure74

Ok guys.. I left parked for a week and had to jump it. The battery has a label of sept 2014 but thers no label to see what brand it is. My car still has the recall on the tail lights problem.... could this be related????
2011 c300 32k miles. thanks MANNY

Dizm

I had the same type of problem as you. Car wouldnt start after a few days. So i was thinking two options; parasytic draw, or bad battery. Got the battery tested two different places. Tested GOOD. Put it back in and hooked an ammeter in line up to test for a higher than normal draw. Was getting only a draw of 8-15 milliamps when the car was off IIRC (not sure what the spec for our w204 but i read that under 50 milliamps is usually ok for most cars).

Brought a picture of the ampere reading to where i bought the battery and told them it has to be the battery thats bad and they gave me a new one. Its been fine since. ive sat it for 2 weeks a coule times and it starts right up!

Moral of my story: Even if they test the battery good it can still be bad. Lol.

If you dont know how to test for a parasytic draw, look it up on youtube. Pretty easy. Lots of multimeters will do the trick. Just make sure its on the right setting and youre not trying to test more than its fused for or youll just pop the fuse.

Hope this helps.

secure74

Thanks !!!!!!! i'm going to replace the battery with a better brand.
Can I unbolt the battery to replace it??? Do I need some kind of
12volts going into the car??? Seems I read you need a trickle charge to
change it out ??? Unless I miss read... Thanks again!!

IGB

Yes.

No.

You may have misread something... I'm not sure how/why you would trickle charge a battery if you are removing it!

Its as if the battery died (whereas you actually removed it) and then you connected a good working battery and started the car (when you installed the new battery)...

secure74

thanks again!!!!