BMW recharge battery with a car

Not recomended, because your car and the other one has computers, take your cables off your battery both of them, negative and positive, this is very important so you will not damage your ESU. or damage the othe cars ESU. connect jumpercables from your other car to your battery, turn on the other car, let car idle for about a half hour, to fully charge your battery provided your battery is in good shape. remove cables from your car and the other car, attach your cables back to your battery than start, DON NOT start your car with other car still attached to you battery, you are risking blowing the ESU on your other car. and damaging your ESU. [email protected]