relinuca

My beloved '09 E350, normally 100% reliable, has a big problem I fear.


Yesterday, I jumped in to run some errands, and it would not start. I fact, it wouldn't even wimper. When I turned the key to start it, numerous dash lights flashed momentarily and the analog clock stated running backwards!! WTF is going on!


The interior lights will not go on, the headlights will not go on, the electric trunk will not open. The only accessory that seems to still work, is the garage door opener button on the rear view mirror!


The original battery has been periodically checked when I get the oil changed at the dealer...each 5K miles.


Right now, my only recourse seems to be to call the dealer on Monday and arrange for a tow truck to haul it in. Not a good story.


Any thoughts will be appreciated.


relinuca

ptkacik

Batteries last about five years. My brother in law had a battery store and said they are all the same and he would put different stickers on them depending on price. The difference, he said, was the warrantee (three or five year), not the guts.

Maybe it is time.

Peter

kajtek1

MB battery can last even 17 years, when we had Spanish-made in ML320 lasting only 13 years.
Still had other=US made dying after 3 months.
Do the test. If you spend some money on dealer service in last 2 years, you qualify for free MB roadside assistance.
They will put new MB battery for you just for part charge.

cetialpha5

Well you can always disconnect the battery and put it on a battery charger and let it charge up. I accidentally left the light on in my car a few weeks ago and it wasn't that much fun. Weights about 60 pounds. Mine is a 2007 AGM battery and I'm in the northeast so temperatures aren't that high year round. The hotter the climate you're in, like Texas, the shorter the battery life. Heat kills a battery. You can get a 2 amp charger for $25 and just leave the battery on the charger, max you should go is a 10 amp battery, those are more in the $40-$50 range. Anyway, I was somewhat surprised, mine was down to 2-3 volts, but was up to around 9-10 volts after an hour or two at 2 amps. After about 6 hours, it up to about 11.7 volts, I think you start getting battery warning messages at 11 volts. Anyway I had to go so I threw the battery back in the car and after a couple hours of driving, the battery was back up to 12.2-12.4 so I didn't bother taking it out to charge up some more. In theory it's not good for the alternator as it places a heavy load on it, but 11.7 was a decent voltage. Should be 12.5-12.7 when it's a new fully charged battery at 70 degrees, mine of course is original so I don't expect to get anywhere near that.

Anyway, probably the best prices are either Advance auto or Autozone, I think the last time I looked, Advance auto was slightly better for some reason when you use a coupon code that takes $50 off the price of the battery and they also install for free, check retailmenot.com for current codes to both. Pepboys also carries it, but they charge a lot for installation so it's not worth it. You could also just take the battery to an auto parts store and ask them to put it on their rapid charger and come back a couple hours later. They usually do that for free.

Zavato

A 7 year old battery owes you nothing. It's time. I've replaced batteries at 5 years even if some juice is left precisely because I don't want to get stuck

cetialpha5

Technically instead of guessing, you should take it to an auto parts store and have them do a load test on it. That will tell you if you can just get away with charging it or if you really need a new one. Of course you'd have to charge it up first in order to do the load test properly.

Oh and I just saw this 8 amp charger on sale at Walmart for $23.

https://www.walmart.com/ip/Stanley-F...undle/38243757

NewShockerGuy

Wait,... tow the vehicle to the dealer for the battery? Do you not have another car you can go and pick up a battery, or have a friend drive you to get a new battery?? Seems extreme unless insurance covers the tow 100% but something like a battery should easily be serviced via DIY, unless it's too heavy, which I will admit the battery in the trunk is quite large but even then, again with the above, a friend and you should be able to pull it out and change it which might be an hours worth of time and that includes driving to get to where the battery is sold.

I've had batteries last 10 years while I've had batteries last 3. Average is 5 years. If you get more consider yourself lucky. 17 years for a battery is unreal. I wouldn't doubt it but there is no way I would ever bank on that number. Unless it was always hooked up to a trickle charger and kept from extreme hot/cold temps that just seems unrealistic to me.

-Nigel

cetialpha5

Yep, he keeps mentioning that, it's the other end of the bell curve but I don't think he realizes it. I don't think it was a daily driver for him so one that doesn't much use will last longer than one that gets used all the time, there's only so many charging cycles that a battery can take. Also it seems like manufacturers are getting worse with battery charging, BMW at one point use to just replace the battery without telling the customer because their algorithm didn't charge the battery enough, that was to conform to CAFE numbers, they're starting to use every trick in the book and that's killing battery life. Expected battery life also depends on the climate, hot areas can toast a battery in 3 years, in cold climates they can last 8-10 years or more. I think a few people have mentioned getting 12 years out of their AGM battery. Mine is at 9 now.

Faniskogen

Charge the battery and drive to the shop would be the best alternative if you are not comfortable with changing it yourself I think.
Or just jumpstart it, even if this does not seem 100% safe with all the electronics in these vehicles.

But if the towing is covered with insurance, then why not

relinuca

FYI-I've changed a few (many) batteries over the years. But...in the current case, the battery is in the trunk, and the ELECTRIC trunk will not open!


Job 1...get the trunk open. Any ideas?


relinuca

mtrevelino

You need to use your metal key. If I am correct, you need to turn the key and use the trunk release lever to open the trunk. It will not just open by turning the key by itself. If you do not know where the metal key goes, look at you license tag and you will see the key hole. It should be above the tag.
Mike T.

cetialpha5

With the metal key in the keyhole, you need to turn the key to the right or left, I think it's to the right and leave it in that position and then lift up on the trunk lid. It should open. Lots of people return it to center and then say they can't open it.

NewShockerGuy

Yep to the two post above. That's exactly what you need to do. I had to do the same thing with our CLK this weekend since I was changing the rear window regulator. I had disconnected the battery but had all the pieces in the trunk. My wife closed the trunk and it wouldn't open but you simply take the metal blade key out, and insert it into the lock. Turn left and boom it opens.

-Nigel

kajtek1

Mechanical locks not used for decade are often frozen, so this is good time for everybody to run to their cars and give locks some exercise.

relinuca

Thanks to MikeT (see above) and my Service Advisor, I figured out how to access and to use my "mechanical" key and open the trunk. (Geez...and I consider myself a car guy!).


FWIW, the Owner's Manual is silent on the issue of how to extract the mechanical key from the FOB. So I used a magnifying glass and eventually figured it out. Phew.


The problem was indeed a dead/bad battery; i.e., after 7-8 years. I called M-B Road Side Assistance and they came out and fitted a new battery...even comp'd me for the svc call. The tech was excellent and said I should be good-to-go for 5-10 years. Hope so.


Thanks to forum members for the help.


relinuca

Stuttgarten

Glad to hear your problem is resolved. A couple of weeks ago, I went to Pep Boys and had them change out my original MB battery which had been in the car since 6/2004. Car was not giving me any problems, but I just wanted it changed for peace of mind. I ended up paying $180 out the door with installation being free for their Bosch Premium Battery
Part #: 49-850BAGM. I negotiated with them dropping an additional $99 charge by agreeing to pull out trunk flooring to allow easier access to battery.

cetialpha5

You should have used their discount code, I think it hovers in the 25-30% range, every once in a while it's up to 35%. Only reason I haven't considered them is because they now charge for installation when it used to be free. The other stores like Advance Auto and Autozone are still free. I can install it myself but hey if it's free, why knock yourself out. Just voting with my wallet/feet.

arto_wa

Sorry but at 11 volts the battery is almost totally drained and it's way too late to have a warning!




It will have 50% state of charge at 12.06 Volts.

kajtek1

In my area PepBoys, Autzone and such are refusing to install batteries on Mercedes.
Too many things can go wrong and hearing those occasional reports that the kid connected battery in reverse and fried $3000 computer sure is not helping.
Bottom line - if you are taking your Mercedes to kids in places like above, Jiffylube, or Speedlube = you are at fault when something happens.

cetialpha5

That's at 70 degrees. I've had 11.5-11.7 voltage readings when the temperature was in the 20-30 degree range. Also that 11 number came from some other thread, that's what someone claimed MB's warning messages kicks in on the dash.

cmriv

battery drained at 11 volts is just as hilarious as a battery lasting 17 years....

however your battery (original) could of been defective yes, but also you could have a draw on your system and or your starter is drawing too many amps sucking life right out of the battery.... in theory once vehicle is running an started, charging of battery system occurs, which is true, but when you shut vehicle off and CGW goes to sleep battery probably creeps down to a voltage that is no longer adequate to start vehicle.... I personally feel as though a battery should last longer then 5-7 years, if it doesn't it's not because of product issue most times (MOST), there is usually a underlying issue that will haunt you later down the road.... Lucky for you though you called road side and got situation handled but keep the tid bits above in mind for future reference.... if for some reason in the coming months you go to start and blahhhhh-nothing, you have something to look back on....

arto_wa

Yes, at 11 volts your battery is not good for much...

cetialpha5

Yeah, except when taking voltage readings, the battery is still connected to the car so that chart doesn't really apply as it's not an open circuit voltage reading, the battery will have a load on it.

arto_wa

Would you please show us a chart that applies, so we can all learn?

kajtek1

Battery testing is whole science. When MB owners tend to do preemptive battery replacement, RV owners don't hesitate to spend $200 for battery controllers and monitors as sometimes 600lb battery bank is not only expensive to replace, but boondocking in the wild, you depend on the batteries with your comfort and sometimes even life.
I have seen new pocket-size gizmos that using advanced computer should test the battery, but can't find too many reviews on them.
I am still using my 50amp load tester when in doubt.
How tricky batteries can be - lately I was ask to move a car that was park for 1/2 year with key in ignition. The battery show absolute 0. Yet with some tricks I was able to recharge the battery with my computerized charger and the battery started the engine....
Per all the theory the batteries once discharged below 10V will never fully recharge, yet the life proves the theory false.