when jumping a dead battery, which car do you start first?

Start the car with the good battery (the “donor” car) first, let it run for a few minutes, and then try starting the car with the dead battery.

Basic order to follow

• Make sure both cars are in park/neutral, parking brakes set, and both ignitions off before connecting any cables.

• Connect jumper cables in the recommended order:
  1. Red clamp to positive on the dead battery.
  2. Red clamp to positive on the good battery.
  3. Black clamp to negative on the good battery.
  4. Black clamp to bare metal (ground) on the dead car, away from the battery.

Which car to start and when

• After cables are connected, start the car with the good battery first and let it idle a few minutes so it can send charge to the dead battery.

• Then attempt to start the car with the dead battery; if it does not start, wait a few more minutes with the good car running and try again.

After the dead car starts

• Keep the once‑dead car running for at least 20–30 minutes (ideally by driving) so the alternator can recharge the battery.

• Disconnect the cables in the reverse order of how you connected them, making sure the clamps do not touch metal or each other while removing them.

Safety reminders

• If you see heavy corrosion, leaking, or a cracked battery case, do not try to jump it; call for professional help instead.

• Always follow the specific procedure in your vehicle’s owner’s manual, since some modern cars and hybrids have special jump‑start points and precautions.

Information gathered from public forums or data available on the internet and portrayed here.