It used to be that when your battery got old or failed you'd go to the store, get a similar cranking power, and pop it in. Fast and cheap. Today, with a modern BMW that has an iDrive knob that controls and monitors lots of electronics, and a computer module that adjusts the alternator current to match the battery type and use characteristics, you need to take much more care in changing your battery. My 2004 530i with 55k miles was over 8 years old with the original BMW battery. So, I decided to replace it before it fails even though it never gave me a problem, yet. I've posted a few pics on the batteries and jumping the car, and you can zoom in for specific details.
The best way to do this, if you don't have a battery programming tool, is to take it to the dealer for the replacement. From various posts, the cost averages about $500, which is $250 for the OEM BMW battery and $250 for the installation and programming. Some say the programming alone can be as low as $100 if you do the rest yourself, but dealers seldom let you leave with a bill of only $100. After researching numerous posts on the web (and there are many, with various opinions), I decided to buy a battery that is an almost exact match to my OEM, and install it myself. I've read that if you match the same battery type and size, battery programming may not be a big issue. I doubt anyone knows how much of an affect variations in battery age or use have on the need for programming. I suspect it's not a big reason for programming. I've read (unconfirmed) that the computer module has a learning function that adjusts to the use of the new battery over time.
A few people suggested you should keep a continuous charge in the system as you replace the battery so it doesn't lose data or trigger error codes in iDrive. So, I jumped my BMW with another battery while I was replacing the old battery, so my car would not lose power or any settings. My BMW manual says jumping the car is ok (see pics). It worked perfectly and was easy to do. You jump the battery system with jumper cables from under the hood, whereas you change the old battery in the trunk. I've read you can buy a "settings keeper" battery device that plugs into the lighter, but I didn't pursue that route and can't verify if it works.
Batteries are rated by whether they are AGM (electrolyte is suspended in Absorbed Glass Mats) or standard Flooded Lead-Acid (FLA, but you won't see that term on the label), ranking Amps (CA, at 32 degrees F), Cold Cranking Amps (CCA, at 0 degrees F), Reserve Capacity (RC), and Amp Hours (Ah). Most batteries don't show Ah, but my OEM did. My BMW OEM is no longer made. It was a Banner (Austria), 900 CCA, 900 CA, 160 RC and 90 Ah, AGM type, that lasted 8 years and was still ticking. After research, I went to Autozone and for $155 bought a Duralast H8-AGM, which is an exact size AGM replacement with 850 CCA and 975 CA, RA 170. Popping it in my car was no problem, but first I hooked up the jumper cables under the front hood to keep the power on. It's a little heavy and awkward to move in and out, but it fits exactly. It also hooks perfectly to my OEM vent hose, with a hole on the left, but since there is also a hole on the right on the Duralast I covered that side with tape. Tools: 10mm and 13mm sockets, with a small extension, and about 30 minutes if you don't stop to take pictures.
There are so many good posts out there on: the exact sizes of BMW OEM batteries; the operating difference between AGM and standard FLA batteries; the way to turn off an "active steering" error (if you have active steering, which I do, but didn't keep your system powered), and other useful posts. I don't know if someone has described a detailed E60 battery install with all pictures (it's not very difficult), but you can see a similar install for a 1998 528i E39 at this link and it's almost the same as for the E60, except my recommendation for the battery jump on an E60. http://forums.bimmerforums.com/forum/showthread.php?t=1162887
The E39 doesn't have iDrive, and I believe it doesn't have the complex alternator charge management system that the E60 does. Incidentally, if your E60 does not have an AGM battery, Autozone sells a standard FLA battery that is the same power and size as the H8-AMG, part number Duralast 49-DL. It's only $105, and most E39s use it as a replacement with a little wiggling in required for the E39, although it is not recommended by Autozone since it isn't an exact fit. For the E60, it's about ½ inch less tall, but the same length and width as the H8-AGM that fits perfectly. For an FLA, I think it would fit fine in the E60. If you switch from AGM to FLA you'd need to program for the new battery type.
The Results: When I started my car with the new H8-AGM battery it was perfect. No errors, no data lost, everything just as before. It runs great and I hope to have another 5 years or more on my new AGM battery. Total cost, about $160 plus a $12 refundable battery core charge. If you change from AGM to standard FLA, or get a dramatically different capacity, you probably must get it programmed at the dealer, or an Indy who has the programming tool. By getting the same type and size battery, and leaving the power on, I got no errors or problems and I think I won't need to program the battery.
If someone can post a collection of useful links on this subject that would be GREAT for folks trying to understand this, without making it their job. Also, it would be nice if someone posts how to buy and use a programming tool for DIY BMW battery programming. As always, comments are encouraged.
GPom
The best way to do this, if you don't have a battery programming tool, is to take it to the dealer for the replacement. From various posts, the cost averages about $500, which is $250 for the OEM BMW battery and $250 for the installation and programming. Some say the programming alone can be as low as $100 if you do the rest yourself, but dealers seldom let you leave with a bill of only $100. After researching numerous posts on the web (and there are many, with various opinions), I decided to buy a battery that is an almost exact match to my OEM, and install it myself. I've read that if you match the same battery type and size, battery programming may not be a big issue. I doubt anyone knows how much of an affect variations in battery age or use have on the need for programming. I suspect it's not a big reason for programming. I've read (unconfirmed) that the computer module has a learning function that adjusts to the use of the new battery over time.
A few people suggested you should keep a continuous charge in the system as you replace the battery so it doesn't lose data or trigger error codes in iDrive. So, I jumped my BMW with another battery while I was replacing the old battery, so my car would not lose power or any settings. My BMW manual says jumping the car is ok (see pics). It worked perfectly and was easy to do. You jump the battery system with jumper cables from under the hood, whereas you change the old battery in the trunk. I've read you can buy a "settings keeper" battery device that plugs into the lighter, but I didn't pursue that route and can't verify if it works.
Batteries are rated by whether they are AGM (electrolyte is suspended in Absorbed Glass Mats) or standard Flooded Lead-Acid (FLA, but you won't see that term on the label), ranking Amps (CA, at 32 degrees F), Cold Cranking Amps (CCA, at 0 degrees F), Reserve Capacity (RC), and Amp Hours (Ah). Most batteries don't show Ah, but my OEM did. My BMW OEM is no longer made. It was a Banner (Austria), 900 CCA, 900 CA, 160 RC and 90 Ah, AGM type, that lasted 8 years and was still ticking. After research, I went to Autozone and for $155 bought a Duralast H8-AGM, which is an exact size AGM replacement with 850 CCA and 975 CA, RA 170. Popping it in my car was no problem, but first I hooked up the jumper cables under the front hood to keep the power on. It's a little heavy and awkward to move in and out, but it fits exactly. It also hooks perfectly to my OEM vent hose, with a hole on the left, but since there is also a hole on the right on the Duralast I covered that side with tape. Tools: 10mm and 13mm sockets, with a small extension, and about 30 minutes if you don't stop to take pictures.
There are so many good posts out there on: the exact sizes of BMW OEM batteries; the operating difference between AGM and standard FLA batteries; the way to turn off an "active steering" error (if you have active steering, which I do, but didn't keep your system powered), and other useful posts. I don't know if someone has described a detailed E60 battery install with all pictures (it's not very difficult), but you can see a similar install for a 1998 528i E39 at this link and it's almost the same as for the E60, except my recommendation for the battery jump on an E60. http://forums.bimmerforums.com/forum/showthread.php?t=1162887
The E39 doesn't have iDrive, and I believe it doesn't have the complex alternator charge management system that the E60 does. Incidentally, if your E60 does not have an AGM battery, Autozone sells a standard FLA battery that is the same power and size as the H8-AMG, part number Duralast 49-DL. It's only $105, and most E39s use it as a replacement with a little wiggling in required for the E39, although it is not recommended by Autozone since it isn't an exact fit. For the E60, it's about ½ inch less tall, but the same length and width as the H8-AGM that fits perfectly. For an FLA, I think it would fit fine in the E60. If you switch from AGM to FLA you'd need to program for the new battery type.
The Results: When I started my car with the new H8-AGM battery it was perfect. No errors, no data lost, everything just as before. It runs great and I hope to have another 5 years or more on my new AGM battery. Total cost, about $160 plus a $12 refundable battery core charge. If you change from AGM to standard FLA, or get a dramatically different capacity, you probably must get it programmed at the dealer, or an Indy who has the programming tool. By getting the same type and size battery, and leaving the power on, I got no errors or problems and I think I won't need to program the battery.
If someone can post a collection of useful links on this subject that would be GREAT for folks trying to understand this, without making it their job. Also, it would be nice if someone posts how to buy and use a programming tool for DIY BMW battery programming. As always, comments are encouraged.
GPom