Itufty2021

Hi All.
I am new to this forum and would like to ask if anyone has experienced the same issue.
I have a 2017 W213 E220 AMG Line which I love to pieces, but if I do not drive it for a couple of days the battery goes flat. If I charge it up it again lasts for a couple of days and it happens again.
Do you guys think it is a battery issue or is there a parasitic fault which is common to this model?
Any information you could supply would be gratefully received.
Many Thanks

ua549

That battery is about 5 years old and is most likely ready for replacement. A battery load test will be definitive. Keep in mind that the electrical system never turns completely off.

Itufty2021

Many thanks for the swift reply.
I will carry out a load test before I bite the bullet and replace the battery.

The_Judge

Same problem with the battery in my 2018 E400C due to the very limited driving I've done since the pandemic began (a whopping 899 miles so far in 2021 — 99% my work activities are now by phone or Zoom). If I take it for a drive of say 20 miles or so, the battery will stay charged for a few days, but after that I start getting the "start engine, see user manual" message whenever I get in the car. I can start the car and let it idle in the garage for an hour (garage door open, of course, key FOB removed from car and car locked by using the Mercedes Me app, which requires using the app again to unlock the car), and that will eliminate the problem for a day or two. But that's not worth the waste of gas, the unnecessary pollution, or the wear and tear on the engine, so I will look into a replacement battery when I take the car in for its annual service in a couple of weeks. Or maybe I should sell it and just call Uber or Lyft whenever I need to go somewhere.

TimInCA

Battery Tenders help keep batteries maintained when vehicles are not driven frequently. I use these on my ICE vehicles.

JTK44

I think you may be onto something!

JTK44

I think you may be onto something!

Seriously, before we sold our 2008 Porsche Boxster, we were replacing batteries every 18 months at $300 a battery. We were driving less than 500 miles a year. A battery tender solved the problem. When we sold the car, the battery was already 5 years old and in perfect condition.

ua549

I have a quick connect setup for a battery tender. My '18 E300 (built June 2017) trips are rarely more than 1 or 2 miles each so the tender is used frequently. Driving 2 miles does not provide enough juice to replace the amount used to start the car and run the A/C for such short trips.

The_Judge

I figure my auto insurance and registration costs me about $4.00 per mile!

On top of that, my wife still drives her 1999 C 230 Kompressor, which I bought as a dealer's demo when it was 6 months old with 10,000 miles on it. Now, 22 years later, it has an honest-to-goodness 35,500 miles on the clock and she has no desire to replace it. At least the insurance is more reasonable.

SmokinJoe

Battery is likely shot.
Get a volt meter that can accurately measure dc voltage..
Pop the hood.
Measure and note the battery voltage.
Put a charger on it overnight, see how long it comes up to full charge. To quick= no good
If it charges fully (about 13-13.5 v, take off the charger and let rest overnight.
The resting standing voltage overnight should be no less than 12.4 v. If it is less the battery is toast.

ua549

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