By YOUCANIC on Jun 21, 2019
In this article, you will learn how to replace a BMW battery yourself.
These instructions include pictures and videos clips to help you replace the battery on any BMW. You will also find a link with instructions on how to perform BMW battery registration which is required in most 2002 and newer BMWs.
Signs that you need to replace a BMW battery:
We strongly recommend that you choose a replacement battery with specs as close as possible to the old battery.
These instructions are meant to help all BMW owners who have a 2002 and newer BMW.
In newer BMW you will find the battery in the trunk, on the right (passenger) side. If you have a station wagon BMW, the battery is in the trunk floor. Remove the liner to expose the battery.
Start by disconnecting the negative battery terminal. Loosen the 10 mm nut. Pull the cable away from the negative battery terminal.
Next, disconnect and remove the positive battery cable. You will need to lift up the red plastic cover to find the 10 mm nut you need to loosen up.
The battery is held in place with a bracket on the side and a top bracket. First, remove the top bracket by removing two 13 mm bolts indicated by the white arrows shown below.
Now it is time to remove the old battery. These batteries are extremely heavy. Ask for help to lift up the old battery.
Carefully lower the new battery in place and make sure it is sitting properly.
Reconnect the bracket brackets. Do not over tighten them or you will crack the battery housing. If you are installing a lead acid battery make sure to connect the vent hose. This is necessary so that gasses from the vent hole don't build up inside the trunk.
Use a battery terminal brush to clean the battery clamps.
Connect the positive battery terminal first.
Connect the negative terminal last.
Now it is time to register the new battery. The BMW battery registration process resets your vehicle’s battery charging history. It deletes any stored battery and temperature statistics for the previous battery. Vehicle odometer reading won’t be lost during the process.
Current odometer reading which indicates when the battery was replaced will be stored in the DME module. For this step, you can use a scanner such as Foxwell NT510 for BMW, but Carly for BMW is also a popular choice.
Follow these step-by-step instructions on how to register a BMW battery.
The average cost to replace a BMW battery yourself ranges between $250 and $350.
You will spend $150-$200 on a new battery. In addition, you will spend around $100-$150 for a BMW scan tool.
For more information read this article on choosing the best aftermarket battery for BMW.
Replacing a BMW battery at the dealer typically ranges between $450 and $580.
Here are a few tips that will help you with the battery replacement process.
If you need to disconnect the negative battery terminal to perform maintenance on your BMW you don't need to perform battery registration upon reconnection. Assuming you reconnect to the same battery.
No, you do not need to register your old battery. The DME module has all the history on this battery and knows how to charge it. You will need to set the clock, synchronize windows, sunroof, and other memory functions.
If you accidentally triggered a warning light, you will need to read the codes and clear them using a BMW scan tool.
Typically a BMW alternator will charge the battery using 13 volts to 14.3 volts.
Typically this is caused due to a bad alternator or a battery that may have a bad cell. Perform a charging system test. Parts stores such as Advance Auto Parts and Autozone will do this test for free.
It could be on for various reasons but the most such as a bad alternator, battery, voltage regulator, power module, etc.
This is often caused by a loose battery terminal contact. Check and retighten or clean the battery cables that connect to the positive and negative battery terminals.
Yes. Make sure to perform coding to let the DME know you have installed a higher capacity battery. You can also install a lower capacity battery.
Yes, you can. Make sure to code your BMW so it knows battery type has been changed. Perform battery registration as well.
No. You will need a BMW scan tool such as Carly for BMW, Foxwell NT510, INAP, BMW Scanner etc.
In some cases, you may notice that the airbag light is on after changing the battery. This is often caused by low voltage. You will need to use a scanner that can read BMW airbag codes. See what the codes are. If they are stored codes just delete them.
You can but the OBD2 scanners used at Autozone and Advance are generic code readers and aren't able to read multiple BMW systems. You will need a scanner that can read BMW specific codes.
If you are having problems after replacing the battery on a BMW, it is very likely that you may have had a short between the positive and negative terminals during the installation process. Check fuses first and scan for codes using a scanner that can read BMW specific fault codes.
We can't say for sure. Most BMW models starting in 2002 need battery registration. Some models didn't require it up to 2005. Call your BMW and verify.
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