ratfancy

OK -so I had to jump my car one day. Got a new battery (after only 2 1/2 years, still had a full warranty). My husband thinks there is a parasitic drain. I took it to my shop, they tested on two different meters, and waited 30 minutes and tested again, and found no problem. However, my husband checks the battery charge every day, and after short trips it settles on 71% charge. Is this normal for my 2011 E350? Wouldn't that be low for a very cold state, like Minnesota?

Sunnyslope48

71% SOC is very low for any car. Ask your dealer to adjust the charge rate. Could be mechanical as in defective alternator, or just an adjustment of the ECM. I recently took my car in for a map update and they found that the charge rate was low and made the adjustment.

thefisch

These cars can eat up batteries especially during short trips thanks to the variable logic of alternator. My last battery didn't make it to 3 years and I found that the alternator always kept the battery at around 60-70% SOC no matter if I had just used my trickle charger. There are other threads that go into more detail if you're interested but your experience sounds 'normal' to me.

ratfancy

But if you live in Minnesota, don't you need 100% of cranking amps when it is 40 below zero?

El Cid

Good luck. I have had problems since my car turned 4 years old. Dead battery at 48 months and one week (warranty expired by one week). New MB battery i paid for came with 3 year warranty so I replaced at 36 months and then replaced that one at 36 months with one that has a 24 month warranty. At 11 months old, it died. MB Roadside Assistance came out and tech jumped off battery and told me to let it run two hours. Then take to dealer ASAP for new battery. He would have installed new one, but I was second call of day and first call got only battery he had. Service Manager said NO WAY on replacing battery or anything else. Contacted MBUSA Customer Assistance - No Way going to help - take it to dealer (for third time for same problem). Called SM- why bring it in, you know the answer.
There is an MB/Daimler document establishing that the light switch for my particular model causes a battery drain, but MBUSA not willing to fix it even though I first complained while car under warranty and the document was in the system.
Have had the Xentry tests run at least twice and they cannot find a "fault stored" so dealer and MBUSA refuse to do anything.
The Best or Nothing? I think not.

kbob999

Do you, or anyone else, have a DIY on this adjustment using Xentry? I'd like to adjust this on my E350 BlueTec.

I have had the original battery die at 4 years, then had a completely dead battery after a trip to the store that was cured with a jump.
No parasitic drain that I can find, but there must be one lurking somewhere.

I now keep the car on a battery tender when in the garage, and it always needs juice when I plug it in.
If I can adjust the charge level it would keep the battery at a more ready state when needed, which is basically always.

ratfancy

Exactly my experience.

El Cid

This should not be necessary. I have had non-MB cars go as long as five years (maybe longer) before changing batteries and these were OEM batteries. Never had one to die before replacement. Nor have I ever used a battery tender, charger, etc. As I noted above, my current M-B battery died after 11 months. M-B dealer says nothing wrong with it. Same one who says cannot find a battery drain, switch defect, etc. Although he did recommend I stop using the Off switch and instead use the Auto switch. To me this seems to indicate there is a known problem with the switch. The problem was reported to dealer when car was under warranty.
As I noted before, I do have an M-B/Daimler document indicating a problem with my particular type switch, which was not used in later versions of "E" Class.
Been all the way up the chain with MBUSA, to include the CEO. He turned it over to the same Executive Referral Manager who previously rejected my complaint. He rejected it again.
Interestingly, they are basically saying it is now out of warranty and they will not repair it under warranty. They are not saying I did not report when under warranty, the document I sent to them is not valid or that the switch is not defective.

ratfancy

I would like to use the "OFF" switch for my headlights - but I don't have that switch! Go figure! See https://mbworld.org/forums/c-class-w...ghts-w204.html

El Cid

It was only on the early (2209 build date) 2010 models. Not sure why. Think it was a carryover from the W211. It is nice to be able to turn everything off, but as I discovered, it really doesn't. Especially if it is defective and MBUSA/Daimler refuses to fix it.