Charge BMW Dead Battery the Right Way

The battery of a BMW is typically charged through regenerative braking or the alternator while the engine is running. However, if the battery has run down completely, it can be charged using a charger. It is important to consult the owner’s manual for specific charging instructions and recommended battery charger specifications for the particular BMW model.

The best way to charge a BMW battery is to use a trickle charger and access a power source. First, ensure the car is turned off, and the battery is accessible. Then, connect the trickle charger’s positive lead to the battery’s positive terminal and the negative lead to the negative terminal. Finally, plug the trickle charger into a power source, such as a wall outlet, and turn it on to a low setting. The charger will slowly deliver a low-level current to the battery, returning it to a full charge. Be sure to monitor the process and stop the charging once the battery is fully charged to prevent overcharging and damage to the battery.

What you will need

CTEK (40-206) MXS 5.0-12 Volt Battery Charger and Maintainer with (56-915) Black Bumper Accessory

Charges Batteries Up To 110Ah. Maintains Larger Batteries Up To 160 Ah; Unique Reconditioning Mode, Built-Intemperature Sensing Capabilities

$125.61

• 12 Volt Battery Charger
  • Recommended CTEK CTEK56 Battery Charger.

Procedure

The proper way to charge a BMW battery is by using the jump start terminals under the hood.

1. Open the driver’s door using the emergency key found inside the key fob.
2. Pull the hood release twice and open the hood. 
3. Locate the positive terminal under the engine bay.
4. Connect the red clamp from your charger to this post. 
5. Locate the negative terminal under the hood. BMW has a designated copper post. If you can’t find the negative (ground) post, connect the black clamp to one of the strut tower bolts. 
6. Determine the battery type. The battery type is printed on top of the battery. The battery type will be Regular/Lead Acid/Flooded or AGM. If the battery has a black case, it is an AGM battery. If the battery has a white case, it is a regular or flooded battery.
7. Plug your charger into a wall outlet or extension cord.
8. Allow the battery to get charged or stay fully charged. Do not keep the key in the ignition while the battery is charging. If you are charging a fully discharged battery, it can take up to twenty-four hours to charge your BMW battery.

BMW batteries are used even when the car is turned off. Typically, it takes 15 to 30 minutes for all BMW systems to go to “sleep.” Even when the car has entered “sleep mode,” 0.1-0.5A is still drawn from the battery.

BMW Charge Battery Warning

The “BMW charge battery warning” means that the battery is discharged faster than it can be charged. This warning can indicate that the alternator, which charges the car’s battery while the engine is running, is not functioning properly. This could be due to a failure in the alternator itself, a problem with the drive belt that powers it, or a fault in the electrical system. The warning light will appear on the dashboard, indicating that the battery is not being charged and may soon go dead, which could result in the car stalling or failing to start. It’s recommended to have a professional mechanic diagnose and repair the issue as soon as possible to avoid any further problems.

Symptoms

• Car won’t start
• Battery Warning Light on
• Airbag light on
• The battery dies when parked for an extended time.
• Instrument Cluster Warning Lights on

Frequently Asked Questions