I have an 83 SL500 Euro import that i somehow killed today. I know nothing about this car. The battery is so old that it wouldn't hold a charged and remained as an open circuit. I hooked jumper cables up to my truck, then to the battery cables of the car. Yes, the positive and negatives were correctly aligned. The car successfully started once and ran for 30 minutes. I shut the car off and went inside. I came back out, never removed the cables, and tried to start the car again. It turned over once, then everything died; no power to anything in the car. The ohm meter showed a complete circuit between the negative and positive cables and i still had 14 volts at the ends of the jumper cables. WHAT HAPPENED?!