Jump-starting the car isn't working

Symptoms

• No change after connecting jumper cables
• Clicking continues even with jumper cables connected
• Jump pack shows low charge or error
• Lights come on but engine still won't crank

Likely causes

• CommonBattery too deeply discharged to accept a jumpA battery drained for a long time may need direct charging rather than a quick jump.
• CommonPoor cable connection or wrong polarityLoose clamps or connecting positive to negative won't transfer power properly.
• PossibleJump pack battery too weak or faultyPortable jump packs can lose charge over time and fail to deliver enough current.
• PossibleBad starter or major electrical faultIf the battery itself is fine, the problem may be the starter, not the battery at all.
• PossibleCompletely dead or damaged batteryA battery that's cracked, frozen, or fully sulfated may not accept any charge.

What to do

1. Double-check cable connections: red to dead positive, red to good positive, black to good negative, black to unpainted metal on the dead car.
2. Make sure the donor vehicle is running and given a couple minutes before trying to start the dead car.
3. If using a jump pack, confirm it's charged and connected with correct polarity.
4. Try leaving the cables connected for 5–10 minutes to let some charge transfer before attempting to start.
5. Listen for any change in the clicking or cranking sound, which suggests partial power is getting through.
6. If there's truly no change at all, suspect a bad ground, disconnected cable, or a problem beyond the battery.
7. Have the vehicle towed to a shop if repeated jump attempts don't work, rather than risking damage to electronics.
8. Ask the shop to test the battery, starter, and connections to find the actual cause.

Tools and parts

• Jumper cables or jump pack
• Flashlight

When to call a pro

If multiple jump attempts fail with correct connections, have the car towed rather than repeatedly trying, since this could point to a bigger issue than the battery.

Safety