It all used to be so simple. “Hey fella, you need a jump?” they’d say. “Boy, howdy, do I!” you’d reply. They’d pull up nose to nose with your car, chuck on some jumper leads, and get you on your way. “Forget that!” said automakers. “Let’s make everything different.”
They put the batteries somewhere else. Where? We’re not supposed to know! We’re dirty little consumers who are too stupid to be trusted with three volts, let alone twelve angry ones! Why, if we dared to jumpstart a car or change a battery ourselves, we might burn the whole car down. Best to hide the battery away from curious little hobbits.
It honestly ticks me off so much. My 2007 BMW E90 buries the battery deep in one side of the trunk. My old MX-5 did the same, and you had to ensure that vent hoses were hooked up so gases didn’t leak out and rust the inside of the car to pieces. My Mercedes puts the big box of acid right under the rear passenger seat along with a bunch of fuses for easy ridiculous accessibility.
I know, I know. I’m being overly harsh. Automakers have granted us some conveniences to ease the pain. They often put nice big 12-volt and ground terminals under the hood for hooking up jump leads. Batteries are often maintenance-free, now, too, so we’re not sloshing about water and acid every six to twelve months. Hiding the battery somewhere inside makes it less likely the terminals will get all gross and corroded. And yes, putting the battery somewhere deeper inside the car reduces the chances it’ll burst open, leak, or catch fire in a crash.
But still, I hate it! I hate it so much. I hate it at breakfast, I hate it at lunch. I hate it on Mazdas, and Jaguars, and Nissans. I hate it on Mercs, and I’m filled with derision. What rude designer approved this decision?
Honestly, I hate it because I drive hoopties. I drive beat up old cars and weird German ones, and I know one day, I’m going to have to change a battery. When that day comes, I won’t just be able to pop the hood and get it done in five minutes. Instead, I’ll be pulling off seats or interior trims, then I’ll be unbolting some whackadoodle battery topper panel and trying to wiggle the thing free. The whole time I’ll be trying not to short out the battery to the chassis while unbolting the terminals. That’s much harder to avoid when you’re wrestling around behind the rear wheel well!
If someone else is servicing your car, or you’re only looking at the battery now and then, it’s probably fine. You don’t even think about it. But for me? Every time I’m troubleshooting something and I’m told to “check the battery” I wince just a little bit. Have pity, and for all of our sakes, make them put the battery back where it’s supposed to go.
Lewin out.
Shots fired! This is wrong wrong wrong wrong! I will grant that the under-seat battery in the Mercedes is bad. This is the worst place to put a battery and I also don’t like it. But having a battery in the engine bay? Also bad. There’s too much heat cycling, it’s annoying to try and jump a car on the side of the road, and the area isn’t protected.
Just put it in the trunk! My E39 has a battery in approximately the same place as your E90 battery and it rules. I can park my car nose in and my car can be jumped easily without having to move the car. If my car does on the side of the road, someone can just pull up right behind me and give me a jump without 900-foot jumper cables or trying to point the nose in the other direction.
Also, let’s not forget the big reason why this is being done in certain cars: weight balance. The battery in my E39 weighs approximately 45 pounds. It’s a big boy. The engine in the E39 weighs way more than 45 pounds, meaning that’s a lot of weight over the front nose which, dynamically, isn’t great. Thanks to putting the battery in the back (and a few other things) my E39 BMW has a nearly 50:50 weight distribution and it feels ideal to drive. So, my argument is not to put all batteries in the front, but to put all batteries in the trunk! -Matt Hardigree
Image credits: Lewin Day, Varta
I own or have owned cars with stock battery locations under the front seat (’37 Plymouth), behind the passenger seat (‘74.5 MGB), under the rear seat (’74 and ’77 Beetles), under the rear glass (’69 Sonett V4), in the rear engine compartment (’65 Corvair), and in the front engine compartment (several), but overall I agree the battery should be in the front. Only the battery, that is, nothing else (’78 and ’80 KV Mini 1):
https://live.staticflickr.com/65535/53604358950_a6554594cf_o.jpg
My MGB was also a 74.5. It matters!
It certainly does, particularly when looking for parts.
Mine was a pretty good tow rig:
https://live.staticflickr.com/4103/5072064860_872de135d8_o.jpg
There are good places and bad places to put the 12v battery. I don’t think it’s specific to a front vs. rear scenario.
Some examples:
Chrysler Sebring batteries are in the front… but go ahead and take a look at where…:)
Volvo S60s (and I think S80s too) had the batteries in the trunk, in a central location, very easy to change out.
The GR86 has it in the front. Being a sports car with lackluster F:R balance, it could have been put in the trunk, but I’d rather have the extra trunk space and ease of service from the engine bay where it resides.
To the point about safety: growing up, friends of the family owned a car dealership, one brand of which was MB, of which he was a massive fan. When the LS400 first came out, they felt pretty threatened and, after returning from a trip to Germany to meet with MB, he showed me the main thing that set MB apart from the Lexus. The MB had two firewalls and the large major components were staggered in installation so that in a frontal impact, the front could compress farther without those components lining up to march into the passenger area (plus the extra protection of the second firewall). The battery being moved out of the engine bay was a part of that philosophy. Lexus didn’t so that. Of course, the Lexus was cheaper, well made, and would become legendary for reliability.
My 2004 Audi Allroad had it in the front – sort of. It was right under the front edge of the windshield, and to get it out you had to unbolt a cross member, and it felt like it weighed about 100lbs! Thing was farking huge!
Oh, and another wonderful Audi idea – there was a large drain directly under the battery tray that would clog up with leaf debris and leak water into the cabin when it rained. Getting that battery tray out so you could clean out the drain was a major job!
So yeah, not just placement, but accessibility is an important design criteria……
Battery in my ’08 Cayenne is under the drivers’ seat, and to make matters worse is the biggest car battery I’ve ever seen-almost like a semi-truck battery. So I feel your pain I put toff replacing it until it was so bad it was needing to be jumped in cold weather because it’s such a PITA. And of course it has some stupid Porsche/Audi specific fasteners to hold the seat down as well.
Weight distribution baby!!!!! But really it all comes down to how well the placement is integrated, not raw location. There are plenty of front mounted batteries that are very dumb to access and or replace as well. Let’s not forget Chryslers wheel well mounted ones…technically the front of the car….
Oh man, I dated a girl years ago who had a chrylser cirrus with that stupid battery, I didn’t believe her when she told me it seemed so incredibly stupid. That car also required semi-special tools to replace the headlight bulbs which imo should have been illegal.
I agree. To make matters worse, BMW routes the sunroof drain right over the battery. I’ve had to replace my battery once because it floods the well the battery sits in, causing a short. To make matters even MORE worse, they put a dumb cubby directly above the batter which ALSO fills with water, which eventually spills over directly onto the battery.
tldr; I need to clean the sunroof drains in my ’06 Wagon, but I don’t know how or where they are. This should be so much simpler.
The trunk is better with jump terminal up front. The only issue I had with that configuration was my Dodge Magnum RT. The hatch was electric release only with no bypass outside, my jump box was in the “lower” floor area back there and I had to lay the seats down and really work to get the jump box out.
My Volvo has the battery almost inside the rear bumper, which is great for weight distribution. Doesn’t take too long to change out, which only seems necessary about every 7-9 years (hooray for AGM!). There are jump points under the hood which have come in handy for the one time I had to jump someone and (of course) had left my jump pack at home.
As someone who loves to add a little (read: a LOT) extra bass to my rides, I LOVE trunk mounted batteries. Makes the wiring a breeze.
Everybody knows that car batteries belong in the ocean
It’s true.
Science doesn’t lie.
Sometimes cars with batteries under the hood are pain to get at also. *Mentally pictures my 92 Lumina Z34*
Under the back seat in a 2000s GM is alright, as the lower seat cushion lifts off in about .5 seconds.
I’ve changed a lot of batteries working at parts stores, and there are some very dumb places some OEMs put batteries, Somehow the ones in the trunk always annoyed me the most, since they do so much extra work to hide (bury) it where nobody can see it and nothing can come in contact.
I’ve had cars with batteries under the hood, under the trunk, and under the rear seat and honestly, I don’t care. I mean, under the hood is easiest to service but the rest aren’t deal breakers.
I’ll tell you what’s far, FAR, FAR more annoying are the cars wired up for positive earth. Sure, you say it works just the same so why should it matter, because the other 99% of the world is set up for negative earth and hasn’t even heard of positive earth so when you leave your car at the muffler shop and they leave the lights on and run the battery down and hook up their charger they don’t even look to see which post leads to ground the just hook the cables up the way they always have and fry every last circuit in your car. Ask me how I know.
…I mean, then you get to rightfully sue them into oblivion, right?
Not really, the total cost of the car wasn’t more than a couple of grand, hard to ask for more than that.
Hmm. I mean, I guess for expediency one would ask for the value of the car, but I feel like there’s something to be said for asking for damages for negligence, emotional value of the car, lost wages if applicable, etc. But I’m also speculating.
I was a teenager with a 20yo British shitbox so it’d be hard to ask for much more than just the damages. They offered to repair the wiring but honestly I didn’t trust them to do it correctly so I told them to have it towed to my house. My dad and I rewired it, which being British it really needed rewiring anyways.
Worked on a boss’s E-Type that was supposed to be negative earth, but was actually positive . . . or maybe it was the other way around, I can’t remember now. The 4.2 was supposed to have gone to negative, but I’m pretty sure his was the 3.8, so maybe it was negative supposed to be positive. Either way, he had no clue and I ended up figuring it out without blowing anything up (though I could have).
My Miata’s little motorcycle battery is in the trunk and I’m fine with that. My Ford and my Honda both have them in front and since they are the ones that usually have to jump the Miata, all ok.
I will not wade into this controversy, but I have to
make fun ofinquire about the condition of the rear footwells in the picture of the Benz. In front of the battery there’s a jug of coolant and a pair of shoes distinguishable from the carpet only because they’re even more in need of a vacuum and a shampoo, while on the side that should be the driver’s but isn’t there’s what resembles some sort of cup, maybe, and a box whose size, shape and graphics make it look like what a sample size of toothpaste comes in. Fair enough on some of that – it’s not a bad idea to have some pre-mix at the ready in an aging car and because your ancestors stole a chicken during the Regency era or saved up ten quid around the time of the Profumo scandal or something and got to Australia, you grew up with the concept of dental hygiene. Regardless,. have you learned nothing from Shitbox Showdown? Clean up a little before taking the picture.I honestly did not even see the shoes, LOL
I agree 100% but because the car buying public does not inquire about battery location the manufacture will do as they please
The three cars I have which have trunk mounted batteries all have jump terminals in the engine bay up front. You can still jump nose to nose.
My battery in my XJR is in the trunk, but I do have charging points under the hood. best of both worlds to me. Puts that heavy ass battery in the trunk, still have the functionality under the hood.
I’m convinced that in the late 90’s – early 2000’s Mercedes hired electrical engineers from Lucas.
Also mounting them in the trunk or floor gets the battery lower which is good, unless you ever had to lift the battery out of Saab with three broken ribs
You almost gave me a heart attack when I thought you were talking about high voltage EV batteries in the front of a car. Every packaging and CAE person in the world probably did too.
Honestly, I don’t even bother jump-starting cars the old way anymore. I carry around a $50 jump pack. If someone needs a jump, I walk over and hook up. Easily one of the best tools I own. Last year, I helped out an older fella after he let his battery drain. He was blown away like I brought over a box of magic.
There’s no song and dance of lining up cars, hoping your crappy cables will make a connection this time, or any chance of screwing up your own car. One time, I jump-started a pickup truck using one of my Smarts, and oh boy did the transmission computer not like that.
First- and second-generation Smarts store their batteries in the passenger footwell. I mean, where else were they going to go? You just pull back the carpet, remove a foam piece, and boom, you have a nice working area.
This
I have a decent jump box for each car. Set a reminder monthly to check/charge them. Peace of mind
—don’t bother with the jump box/air compressor combo ones: I’ve had 3 fail. The Slime brand compressor is decent for occasional use & fairly cheap
Before I add a master disconnect switch to my 97 Mustang, which has an ever so slight parasitic drain (so small the drain does not register on a voltmeter), I had the bright idea to jump it with my Maverick…hybrid. I was a little desperate and the hybrid’s 12-volt battery is easily accessible underneath the backseat’s liftup bench. Lo and behold it worked perfectly and the Maverick never even through an engine code. I’ve since purchased a jump pack and thankfully, I’ve never had to use it. At least I know the Maverick is up to the task…in an absolute worst-case scenario.
Question is, does the drain register on an ammeter? (Maybe a different setting on your “voltmeter”, do not try this setting with the leads across the battery or from hot to ground because bad things will happen). Ammeter leads will definitely go between the battery terminal and the battery connector. If that doesn’t show a drain, the problem is something else. It will probably show a small drain, due to stuff that doesn’t ever shut off like the radio’s memory or perhaps the ECU.
Yes, these are good, if it is not too cold out, which is when batteries are weakest (including the jump pack that is now 10 degrees). And if you don’t mind adding another set of rechargeable batteries to the list of batteries to keep recharging.
I bought jump packs for my kids cars, but my beefy jumper cables continue to ride in my trunk, neglected, forgotten, and waiting for their next hero act.
I’ve never had one of these “fancy battery” cars personally, but I’ve heard rumors on the Dodge Stratus (early in the days of the cab forward design ethos), the front tire had to be removed to change the battery?
The Journey required the tire wheel liner and a bunch of other stuff removed
A few decades ago I had a 2001 Bonneville, which has the battery under the rear seat. Fortunately, it had a jump point under the hood – a positive terminal to clamp to, and then you clamped the negative terminal to the alternator bracket, which has an embossed “(-)” on it.
Unfortunately, I found out that my car was missing a little cover that went over the battery terminals to keep it from shorting on the seat Springs when one of my 6’9″ friends climbed into the back and then a minute later noted his butt felt like it was on fire. Luckily, we were still in the parking lot and I knew exactly what was happening and pulled the seat out before it caught fire and burned the car down. Needless to say, I’m not a fan of the battery under the seat.
As long as there is a key for the trunk, or other manual way to open it when the battery is dead, I think it’s fine that it’s back there, especially for weight distribution. Plus, if my Miata had the battery under the hood, there would be no room for the supercharger or its large cone filter and heat shield housing!
Under the hood is usually fine, except for when cold weather kills the battery, and the hood is frozen shut, so the car is just stuck there until it melts free. This has happened to my Saabaru at least twice, which is two more times that I would like it to have happened.
At least none of your batteries are in the fender, like some Dodge/Chrysler cars from the 90s/2000s!
Don’t forget: some (all after F series?) newer BMWs needs to be coded after a battery change.
That is a real PITA if you don’t have easy access to ISTA thru a shop/dealer/old laptop used only for diagnostics with enet cable.
And although Matt’s counterpoint is valid to me, one of the reasons BMW buries the battery in the trunk is to avoid jump starting by pluging directly to it, because it can fry its precious eletronics.
An E39 should fewer eletronics, but they are hard to get. I would use the regular plugs at the engine bay.
You should not mess with any car eletronics, but germans seems to be more sensitive to that.