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How to Tell If Your Battery Is Dead

car broken downBefore you try jump starting a car, you need to determine that the battery is the reason the car isn’t starting up. If you turn the ignition and hear the engine cranking, a dead battery isn’t your problem and jump starting it won’t do a darn thing. However, if you turn the key and the car does absolutely nothing, then there’s a good chance you have a dead battery on your hands and jumping it may be your ticket to getting back on the road. Whether you left the lights on or it’s that the battery is just old, sometimes even the most reliable cars won’t start.

With a little planning, though, you can be prepared if you ever need to give your battery a charge.

Using Jumper Cables


DO NOT TOUCH the metal clamps to any metal other than as described below. Doing so could cause an electric shock.

Before you hit the road, make sure you have jumper cables in your emergency car kit. Once someone has arrived with a working car that you can use to charge your dead battery, try the following steps:

  1. Park the front of the two cars close together but make sure they don’t touch.
  2. Make sure both cars are turned off.
  3. Connect the positive jumper cable (usually red) to the positive terminal (usually marked with a plus sign) on the “dead” battery.
  4. Connect the other end of the positive cable (+) to the positive battery terminal on the vehicle with the “good” battery.
  5. Connect the negative cable (usually black) to the negative terminal on the vehicle with the “good” battery.
  6. Connect the other end of the negative cable (-) to some large metallic part of your car’s engine block.

NEVER connect it to the negative (-) post of the “dead” battery as it will cause sparks.

  1. Check that the cables are not near any moving engine parts.
  2. Start the “booster” vehicle and let the engine idle for a few minutes.
  3. Start the vehicle with the “dead” battery.
  4. Remove the cables in reverse order (negative from “dead” battery, negative from “live” battery, positive from “live” battery, positive from “dead” battery)

Make sure to keep the jumped car running for at least 30 minutes to give the battery sufficient time to recharge.


If you are not comfortable performing any of these steps, call a professional for assistance.

Call Roadside Assistance

Many auto insurers now offer roadside assistance plans for their customers, which often provide help with common situations, such as breakdowns, flat tires and dead batteries. It can be a relief to know professional help is just a call away (or click, as some providers offer apps as well) if your car won’t start. If you don’t have this service, you may want to consider adding it to your auto insurance coverage or purchasing a roadside assistance service plan.

After your car is running again, remember that a jump is meant to restart the disabled vehicle, not to recharge the battery. It may be a good idea to put the jumped battery on a battery charger, which you can buy at an automotive store, as soon as possible to help ensure that it’s charged to full capacity.

If you’re unsure about the long-term health of your battery, consult a mechanic or a professional at an automotive store for advice.

Trust your local experts.

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