[Billfitz]

[chollz]

I have a 2016 340i and just hit 50,000 miles. Drive it 6 days per week and it is still the original battery that came from the factory.

I am starting to get "battery discharged. Start engine" message. Some times it will not turn over on the first try and I have to hit the Start button for a second time before the car comes to life. I assume this means the battery is on its way out and I just need to get a new battery. Anything else I should be paying attention to?

[fe7565]

Originally Posted by chollz

I have a 2016 340i and just hit 50,000 miles. Drive it 6 days per week and it is still the original battery that came from the factory.

I am starting to get "battery discharged. Start engine" message. Some times it will not turn over on the first try and I have to hit the Start button for a second time before the car comes to life. I assume this means the battery is on its way out and I just need to get a new battery. Anything else I should be paying attention to?

When your battery is weak, several systems will start shutting down. And you will get a myriad of error codes.

When you replace the battery, make sure you get the same type and close to the OEM capacity. You can go over/under by 5 or so percents. But you also need to register the new battery with the correct capacity in order to get optimal charging, and to avert under-charging which will cause errors again.

[chollz]

Originally Posted by fe7565

When your battery is weak, several systems will start shutting down. And you will get a myriad of error codes.

When you replace the battery, make sure you get the same type and close to the OEM capacity. You can go over/under by 5 or so percents. But you also need to register the new battery with the correct capacity in order to get optimal charging, and to avert under-charging which will cause errors again.

Thanks for the input. I'll take it to a dealership and get a new battery. I would probably do it myself but I don't have the hardware to do the computer reset unfortunately.

[fe7565]

Originally Posted by chollz

Thanks for the input. I'll take it to a dealership and get a new battery. I would probably do it myself but I don't have the hardware to do the computer reset unfortunately.

Depending how you are inclined to troubleshoot your car in the future, may want to get some inexpensive tools, like a ($20 on Amazon) ENET cable that you can use with the free ISTA+ (can get it from this forum).

Most car diagnostics phone apps (need a wireless dongle) like Bimmercode, Bimmerlink, Carly, etc can register the battery. An ELM327 Bluetooth that works (for me) with Bimmercode is about $3 on EBay.

Compatible battery from Walmart is about $140-$170-$220.

[chollz]

Originally Posted by fe7565

Depending how you are inclined to troubleshoot your car in the future, may want to get some inexpensive tools, like a ($20 on Amazon) ENET cable that you can use with the free ISTA+ (can get it from this forum).

Most car diagnostics phone apps (need a wireless dongle) like Bimmercode, Bimmerlink, Carly, etc can register the battery. An ELM327 Bluetooth that works (for me) with Bimmercode is about $3 on EBay.

Compatible battery from Walmart is about $140-$170-$220.

Yeah, definitely thinking about that. I'm going to see what the dealer will charge me. If its outrageous, then I will go down the DIY route.

[Billfitz]

Originally Posted by chollz

I don't have the hardware to do the computer reset unfortunately.

You should. Or do you enjoy paying a dealer $150 or more to read error codes when you can do it yourself with a code reader app? You don't necessarily need a unit like a Foxwell NT 510, but knowing that a dealer would charge me at least $100 to register a battery convinced me to buy one long before I'd need it for that job. It paid for itself the first time I used it to pull codes.

[alohasurftoad]

$170 @ costco
https://costco.interstatebatteries.c...185&Country=US

on amazon, there are numerous bmw obd scanners in a variety of price ranges that increase with functionality. just be sure it can do a battery registration. i have an autophix, which is a foxwell knock off.

many also use mobile phone apps such as bimmercode

[Billfitz]

I have the bimmer-tool Lite app. It won't do battery registration, but it does a lot, including some things that my Foxwell won't. Bimmercode is a must IMO, but it only does coding. Bimmerlink does code reading and battery registration.

[chollz]

Originally Posted by Billfitz

You should. Or do you enjoy paying a dealer $150 or more to read error codes when you can do it yourself with a code reader app? You don't necessarily need a unit like a Foxwell NT 510, but knowing that a dealer would charge me at least $100 to register a battery convinced me to buy one long before I'd need it for that job. It paid for itself the first time I used it to pull codes.

Yeah I got quoted $600 to change the battery. I already got the adapter on Amazon and I'm going to Costco tomorrow to get the battery and install myself. i will get the Bimmerlink app tomorrow as well so I can do the coding.

[pobrienny]

Originally Posted by chollz

I have a 2016 340i and just hit 50,000 miles. Drive it 6 days per week and it is still the original battery that came from the factory.

I am starting to get "battery discharged. Start engine" message. Some times it will not turn over on the first try and I have to hit the Start button for a second time before the car comes to life. I assume this means the battery is on its way out and I just need to get a new battery. Anything else I should be paying attention to?

The alternator could be beginning to fail. Check the output voltage when the car is running. I had that fail before the battery did.

[chollz]

Originally Posted by pobrienny

The alternator could be beginning to fail. Check the output voltage when the car is running. I had that fail before the battery did.

Can I read voltage with the Bimmerlink app or do I need an multimeter? (I think I've got one but would prefer to use the app lol)

If so, what voltage am I looking for to comfirm/deny it is an alternator issue?

[chollz]

Originally Posted by chollz

Can I read voltage with the Bimmerlink app or do I need an multimeter? (I think I've got one but would prefer to use the app lol)

If so, what voltage am I looking for to comfirm/deny it is an alternator issue?

I got into the "hidden menu" on my F30 to get the voltage reading. When the ignition (engine not started) is turned on, the voltage hovers around 11.6. When I try to start it the first time, it briefly flashes and drops down to 4.5. When I try to start it for a second time, it VERY briefly flahses and shows 6.2 and then starts. Once the engine starts, the voltage goes up and hovers around 14.6. Once I turn it off voltage shows around 12.6.

I think this is telling me the battery is indeed bad (not the alternator) and I just need a new battery. Or am I getting this wrong?

Here is a video I took of what is happening:

[Billfitz]

What it's telling you is that when the starter engages it sucks a lot of voltage, so much that other applications including the dash read out don't get their normal allotment. That's perfectly normal. What's not normal is reading 11.6v when you switch on the ignition. That could be the battery, but also could be parasitic power drain. If you charge the battery to at least 12.5 v, disconnect the negative terminal and measure more than a 0.3 volt loss overnight the battery is suspect. You have to measure it with a meter at the battery, otherwise if there's a parasitic drain it will start sucking away voltage as soon as you reattach the negative terminal.

[chollz]

Originally Posted by Billfitz

What it's telling you is that when the starter engages it sucks a lot of voltage, so much that other applications including the dash read out don't get their normal allotment. That's perfectly normal. What's not normal is reading 11.6v when you switch on the ignition. That could be the battery, but also could be parasitic power drain. If you charge the battery to at least 12.5 v, disconnect the negative terminal and measure more than a 0.3 volt loss overnight the battery is suspect. You have to measure it with a meter at the battery, otherwise if there's a parasitic drain it will start sucking away voltage as soon as you reattach the negative terminal.

Got it, thanks for the input. I will try and charge, disconnect neg terminal and then measure it after it sits overnight to confirm it is indeed a bad battery.

[nh90crxsi]

So you can go to orielly auto and buy a battery for about 250 for a p/n 49PLT battery (AGM) install it in the parking lot and use the OBD scanner the store uses for check engine lights and register your battery right there


Boom done!

[chollz]

Originally Posted by Billfitz

What it's telling you is that when the starter engages it sucks a lot of voltage, so much that other applications including the dash read out don't get their normal allotment. That's perfectly normal. What's not normal is reading 11.6v when you switch on the ignition. That could be the battery, but also could be parasitic power drain. If you charge the battery to at least 12.5 v, disconnect the negative terminal and measure more than a 0.3 volt loss overnight the battery is suspect. You have to measure it with a meter at the battery, otherwise if there's a parasitic drain it will start sucking away voltage as soon as you reattach the negative terminal.

Yesterday I charged the battery up to 12.58 V and then disconnected the negative terminal. I went back this morning (over 12 hours later) and measured 12.51 V. Obviously not the 0.3 V loss...

But I did watch another video on YouTube that says if your battery drops under 10V during ignition (which mine does), your battery is bad. I am thinking that is the case and I do not have a parasitic drain issue. It would make sense as this is the battery that came with the car. Its a 2016 MY and now its 2023 so it would make sense the battery could be bad by now.

Here is the video I found on YouTube leading me to believe it is a bad battery. (it should start at the point where he starts talking about voltage drop during ignition, but if it doesn't forward to about 1:40)

[chollz]

Here is the video of me starting my car after the charge... Still dropping under 10V during ignition.

[Billfitz]

Measured at the battery, which takes the power management system out of the loop, that's not good. Mine never goes below 10v.

[chollz]

Originally Posted by Billfitz

Measured at the battery, which takes the power management system out of the loop, that's not good. Mine never goes below 10v.

That would tell you the battery is on its way out, correct?

[Billfitz]

It's not totally definitive, but it's not a good sign either. At seven years I'd be inclined to err on the side of caution.

[chollz]

Replaced my battery. Coded and registered w/ BimmerCode and BimmerLink. All errors have gone away and is starting up immediately as expected. Seems it was just a bad battery. Thanks all for your input. Hope these posts and videos of my car can help someone later down the line...