If the car's own battery is flat, your BMW's engine can be started by connecting two jumper cables to another vehicle's battery. You can also use the same method to help start another vehicle. Only use jumper cables with fully-insulated clamp handles.

Do not touch any electrically live parts when the engine is running, or a fatal accident may occur. Carefully adhere to the following sequence, both to prevent damage to one or both vehicles, and to guard against possible personal injuries.

1.  Check whether the battery of the other vehicle has a voltage of 12 volts and approximately the same capacitance in Ah. This information can be found on the battery.
2.  Switch off the engine of the assisting vehicle.
3.  Switch off any consumers in both vehicles.

There must not be any contact between the bodies of the two vehicles; otherwise, there is a danger of shorting.

Connect the jumper cables in the correct order to prevent sparking at the battery, which could cause injury.

Your BMW has a jump-starting connection in the engine compartment which acts as the battery's positive terminal, refer also to the Engine compartment overview on page 217. The cap is marked with +.

1.  Pull the cap of the BMW jump-starting connection up to remove.

2.  Attach one terminal clamp of the plus/+ jumper cable to the positive terminal of the battery or a starting-aid terminal of the vehicle providing assistance.
3.  Attach the second terminal clamp of the plus/+ jumper cable to the positive terminal of the battery or a starting-aid terminal of the vehicle to be started.
4.  Attach one terminal clamp of the minus/– jumper cable to the negative terminal of the battery or to an engine or body ground of the assisting vehicle.

Your BMW has a special nut as body ground or negative pole.

5.  Attach the second terminal clamp of the minus/– jumper cable to the negative terminal of the battery or to the engine or body ground of the vehicle to be started.

1.  Start the engine of the donor vehicle and allow it to run for a few minutes at slightly increased idle speed.
2.  Start the engine on the other vehicle in the usual way.

If the first start attempt is not successful, wait a few minutes before another attempt in order to allow the discharged battery to recharge.

3.  Let the engines run for a few minutes.
4.  Disconnect the jumper cables by reversing the above connecting sequence.

If necessary, have the battery checked and recharged.

Never use spray fluids to start the engine.