My dad jump-started his car connecting the cables in series.
 

His car died and he called me to jump his car. I connected the negative and positive terminal onto my battery and he connected the positive one onto his. Then he connected the negative part to the metal frame. We tried 3 times but it didn't work. So he connected it to the negative terminal and jumped the car. So, if my car's electric system is completely busted, how long will it take for me to find out? I would have seen him do it if the hood wasn't blocking my view. =(. I tested everything several times and it seems to work fine, but I think some electric component will die on me in the upcoming days.

ummm, so what seems to be the problem then?

Nothing as of now. I'm a car newb, so I was wondering if there is a possibility of messing up my electrical system, drain my car battery, etc.

lol, if something was going to happen, it would have happened when the jump occured.....

problems dont just sit dormant and then decide to come at a later date. youll be fine.

yeah, you should be fine. unless u start messing w/ the electrical, just gotta make sure everythings connected properly.

He connected his positive cable to the positive terminal, and the negative to a metal part of the car? If so, that is exactly how you jump a car off. Most likely he was on a painted part or a part that happened to not be directly bolted to the unibody or motor, so it wasnt getting a ground, which is why connecting to the negative terminal fixed it. That is not connecting in series. The negative terminal is the same as connecting to the block or the unibody, so they are connected in parallel like they should be.

For future reference, the best way to jump them is not to jump them. Connect the cables, and start the car with the charged battery. Let it run for about 15 minutes, remove the cables and then start the other car. Much safer on your electrical systems.

Isn't positive on positive and negative on negative in series? Damn, Physics lol, I forgot.

take the power wires and dip them in water. it'll protect them

lol buddy youll be fine like they said anything that would go wrong WOULD have gone wrong already. and make sure you dont touch the jumper cable ends together when the other side it attached to a battery, and dont touch both the terminals with a piece of metal at the same time, common urban myth is that you will get shocked if you touch both terminals with your hands, FALSE. Just dont touch both with a piece of metal.

//i take no responsibility of anything that may happen\\

One of the reasons it's advisable to ground the negative on the block or frame as opposed to the negative terminal is so you don't explode. What used to happen with older batteries is, when the car wouldn't start and people kept cranking the ignition the battery would release variable amounts of H2 gas. You can imagine what would happen if you connected everything up. Everything would be fine until you closed the circuit by connecting the negative from the good car to the negative pole on the dead battery that was emitting that H2--something akin to the Hindenburg! Grounding somewhere away from the battery will still arc but hopefully no where near the battery

It is not an urban myth that if you touch each terminal you will get shocked. The low voltage of a car battery, combined with the approx 5000 ohms resistance (it can vary wildly) of the human body, only allows for about 2 uA, which is not very noticeable. But the body is a conductor, so if you touch the positive and negative terminal of ANY battery with each hand, there will be current passing through your body, however small it may be (you may not even "feel" it). The resistance of your skin will vary as well depending on time of year and conditions, since moisture content at the surface of your skin changes.

That is parallel. The voltage is still 12V. That allows for more charge capacity, but not more voltage. That is how you should have them hooked up.

Two batteries in series is connecting the negative of the first one to the positive of the second battery, so reading from the postive of the first and the negative of the second you would have 24V. That is not how you want them connected.