Have a 2014 ML350, original battery, time to replace before it craps out on me. Not positive where it sits, only time I've had to jump someone used the postive/negative posts under hood just for that.

Figure it's under some plastic cladding up front, perhaps even in rear storage area as BMW does with some cars. Not even close.

Under. Passenger. SEAT!!! Hello???



WTAF??
Make no mistake, this isn't just any ol' battery.. Oh hell no, this is a 14"x7"x8" behemoth weighing in at 60#. Yes, 60 everfreaking pounds. All buried in a well under seat.

Online videos show how easy it is to replace and some old man doing it in about 7 minutes. I told Deniseair I expected it to take an hour+ and involve lots of cussing and likely an injury. I wasn't wrong.

The process starts with moving seat full forward, then removing cover under seat. THEN you take a utility knife and slice the front edges of the carpet if this is the first time batter has been out (Fig 3 above). Yep, they actually install the carpet OVER the battery because that is a sign of what a genius location this is.

Then you are working to get the 2 bolts tightening clamps loose. Rear/negative pretty easy. Front/positive not so much even though that bolt is canted 45 degrees toward rear. The front terminal is 2-3" up under the immovable part of floor. Of course you're also working just with flashlight now after removing negative.

Bonus points for futzing around with that and closing battery circuit with socket/extensions/handle. Surprising how damn hot a 10mm socket gets in just a moment of that action. Pure genius. Fuck you, amateur.

Hold down bracket is at bottom rear and must have had nuts put on by a three-pointed Feen in the motherland. Loosening easy, getting out not, and you know it's gonna be fun getting back in. Yeah, you're taping nuts into socket to get them in place.

Regardless of my German heritage I'm calling down curses and damnation on MB engineers by now. Everything loose but the fun still goes while you try to maneuver the battery out.
FUCK. YOU!!! OWNER!!!!!

Only way it comes out is lifting up the rear edge through hole that is 2/3 length of battery, slide/lift/pull whole thing back/angle/up/out. See weight comment above. Outside of car - no good angle. In car, bent over with head on seat tugging and grunting to hearts content. The sweat now running off of you isn't helping your grip.

Oh - neither is the blood coming out of the open wound on back of hand by now that you just notice. Pause to clean up that shit before it stains and back to it.

Reverse all that, like putting a 10" puzzle piece in a 9" hole. Want to get that front terminal back on - good luck you loser, that shit will take longer than an entire battery install should.

Instead of returning core for $20 I may have to shoot it full of holes just to get sanity back.

I will not buy a car that does not have a battery they I can change in the parking lot of an autozone with the small tool kit I keep in under 15 minutes.

The video guy did it in 4.44 minutes




Link to original video: https://www.youtube.com/watch?...annel=TheBatteryShop

quote:

Originally posted by HRK:

That's the guy. Screw him too.

If you play the video at double speed, it only takes 2:22.

Looked pretty easy and straight foward to me. But I have to agree that most of todays designers/engineers need to be taken out behind the wood shed. They do this to discourage the owner from working on the vehicles by hoping that you will screw something up and having to bring it back to the dealership to be fixed allowing them to pay their price. ................................. drill sgt.

I hope you replaced the auxiliary battery at the same time...

Really looking forward to doing this soon on my GL. Not

There are a few others that can be griped about, but the next level of pain in the assery is a Toyota minivan.

The battery is located underneath the thing.

All German engineers love to play hind the battery game. When I purchased my Porsche 911 I was told never ever let the battery go dead. It is like a 30 page process in the manual to get to the battery to jump it. You need another battery and must connect that into the car before the systems will let you open the frunk to get to the battery.

When replacing one in an older Mercedes SLK the guy kept says this is the wrong size, can't be. Until the one we pulled out was bigger than the one he put back in. I swear if you did not memorize the steps and turns taking it out there was no way to get it back in without more disassembly

But there is nothing like driving a German engineered car

Uh, yeah... When the instructions for some routine car maintenance start with Step 1: Get a knife and cut open the carpet, then you know some "book-smart but world-dumb" engineer really fucked something up.

If you own a Mercedes and the battery location is the worst mechanical bitch you have about the car to date, count yourself fortunate, lol. Give it time...I'm sure there are all kinds of fun engineering surprises waiting under that hood, and in the electrical system. But I do agree...whoever designed that needs to have his skull stove in with a tire iron.

My 2018 Durango has the battery in the same location...probably some genius idea that got pushed onto Chrysler by the Daimler side of the house...although Chrysler had been putting batteries in idiotic locations long before Daimler was ever in the picture (see late 90s/early 2000s Intrepid/Sebring/Concord).

The real fun thing about my Durango, though, is that it's a squad car. There's a prisoner transport cage with a solid steel wall behind the front passenger seat. I don't know how in the hell they're going to get the battery out when it needs changed, but thankfully it won't be my problem!

Your problem is pretty obvious from watching the video. Were you wearing a lab coat?

IIRC, 1 or more of my grandmother's S-Class (she had 7 in total) had the battery under the back seat.

When I got rid of my C300, it had some error/fault in the charging system.
I figured it was either:
Main Battery - Under the hood, remove 1 trim panel & easy access
Aux Battery: In passenger footwell, IIRC, have to remove/pull back carpeting
Alternator: No idea there, never really looked at/for it.

Loved the car, but that issue, plus a cracked wheel & being just out of CPO warranty, I was a bit glad to be out of it.
The Malibu I'm driving now is very much less dynamic to drive, but considerably cheaper.

Same spot on my wife Jeep Grand Cherokee

HA!
I was just thinking about this with my wife’s Jeep Grand Cherokee and I thought I’d look it up on the same guys website...

Damn the same engineers that designed the MB above must have designed the Jeep GC when it was part of the MB group...

https://youtu.be/7ne0gOK3SPY

While you are in Deutschland, stop over at BMW Motorcycles and try to find out why they are so fascinated with tiny Torx screws.
My entire motorcycle appears to be put together with them.

 
I cannot imagine what the replacement battery costs, with that funny positive terminal. It certainly is not a regular BCI group number. And I noticed that he tightened the clamps to 6 Nm (4.4 lbs ft). That seems awfully light. I do mine to 7 lbs ft and feel that setting is a bit light.

Most people do not realize that the Benz name is German for "bend over".

quote:

Under. Passenger. SEAT!!! Hello???

Mercedes-Benz isn't the only one doing this. I'm seeing it in American cars like the Enclave/Traverse/Acadia as well. Once I did one on an older Buick Park Avenue (or similar GM car of the period, I don't quite remember) that had it under the rear seat cushion. The old battery leaked acid around the positive side terminal and ate a hole through the floor pan of the car. That's right, I could look through it and see the shop floor.

This is probably an AGM or gel type battery, but if it is a conventional lead-acid that outgasses, be sure the vent hose(s) are intact and put back in place.

Like egregore said, we had a 2008 GMC Acadia and the battery was partially under the front passengers seat. However unlike the OP's Mercedes, I didn't have to cut the carpet to replace the battery.