How to Replace Your BMW E90 Battery
Project Time: 1HR
Budget: $200CAD
Tools you will need for this.
Socket sizes 10MM and 13MM
Flathead screw driver
Safety gloves and goggles
BMW battery registration tool
For this example, we will be writing a guide on how to replace a battery for a BMW E90. BMW's sedans have a harder-to-reach battery than their SUV models. Each vehicle battery location and recommended group size battery varies depending on your BMW's model and year. Check your owner's manual or give us a call for any help.
We recommend using an OEM spec or equivalent battery for your BMW.
*Disclaimer. We recommend a professional technicians when replacing your BMW's battery as batteries can be dangerous and explosive.
Make sure it's your battery.
Always make sure it is your battery that is causing a no-start symptom. Test all your lights, both low beam and high beam, to see if they are getting enough power. Worst-case scenario, your starter has failed if all your lights are functioning well.
If you have not been driving as much, we recommend going 30 minutes of highway driving to charge your battery back up. Even after your drive and your BMW's battery indicator is still on or on red, we recommend entirely replacing your battery as your battery is not accepting any charge and it's due for a replacement.
Locate your BMW E90 battery.
For E90s, the battery is in the trunk of your BMW. Located to the rear right of the truck, underneath a cover. If your car is dead and cannot access your trunk, add a secondary power source.
Add a secondary power source for your BMW.
Make sure your BMW has a secondary power source when you are fully disconnecting the battery. This will ensure all your presets, radios, and control modules do not entirely lose power and have some power to them. Otherwise, you may have to reset your presets, and some codes may pop up.
Disconnect the negative cable.
Always start with the negative cable when you are trying to remove a battery. This way, you will not cause a spark and might fry your computer, ending with more repairs.
Remove the top brace.
Unscrew the positive nut and release the power distribution box from the battery.
Now unscrew the positive nut and release your power distribution box. We recommend using a flat head driver to pry the hold-down clamps on the power distribution box.
*You may get away without disconnecting the distribution box. If your BMW's battery is a group H7/H8. We recommend to fully disconnect your distribution box for easier removal and installation.*
Remove the last hold-down.
To the very right side of your battery where the negative post is should be another hold-down clamp; remove it.
Put aside both positive and negative cables, be careful as there is still power on the vehicle.
Make sure none of the wires/posts touch each other, or there will be a spark.
Remove the battery.
Carefully remove your old battery. Make sure you don't cause any stress/tangle on the wires when trying to remove your old battery.
Inspect and clean terminal posts.
We recommend cleaning your battery cable post with a battery wire brush. Any metal brush will work; always make sure you clean your posts for a great connection.
Put in your new BMW battery.
Start prepping to put in your battery. Either have someone hold the positive distribution cap or use a bungee cord so it will not get in the way once you have replaced your battery. We also recommend to use your manufactures recommended battery size. For everyday purposes we'll recommend putting in the same spec battery and for track purposes, we recommend going with a lighter battery.
Do everything in reverse, positive first, negative, and then your hold-down clamps.
Put on your BMW battery positive first and snap in the power distribution box. It should just clip on your battery. Then your negative cable and all the hold-down clamps.
Registry your new battery.
Registering your battery is essential for most modern BMWs; skipping this step may cause your battery to fail prematurely. If you do not have a registration tool, give us a call, and we will register your battery for you.
Remove your secondary power source.
Always disconnect your negative jumper cable first then your positive cable.
Start your BMW.
Once you have started your BMW, double-check your work and make sure everything is secure. And test all your windows, sunroof, and headlights, etc.
If your BMW still has a battery indicator light on (yellow), drive around for a bit to charge up your battery and so your computer can reset itself. This may also be a good time to recycle your old battery.
If your BMW has a red battery light on, have your alternator checked.
You are all done.
Enjoy once again your ultimate driving machine. Don't hesitate to book online or contact us for any help to replace your BMW's battery.
TL:DR
Make sure to have a secondary power source. Otherwise, you may have to reset your presets.
Disconnect the negative cable.
Remove top brace.
Disconnect the positive cable.
Release power distribution cap.
Remove the last hold down.
Replace and install the battery. Do everything in reverse order.
Registry your battery.
For any assistance or to book your BMW E90's battery replacement.
Give us a call at 1-866-709-2116 or contact us online and one of our BMW technicians can be on their way.