I don't know what kind of car do you have - but let me suggest an important thing.
Whenever you need to jump-start your car or just reconnect the car's battery, make sure the ignition key is in OFF position before the cables are securely connected!!
If you leave it ON you can easily fry computers.
It's a big and repeating problems.
The latest one I have seen was a '07 BMW X5. $$$$$$$ !!