You know how to deal with a dead car battery. A simple quick start should get you back up and running, but what happens when it doesn’t? When the car doesn’t start with a jump, you face bigger problems than expected.
If your car won’t jump start, there may be a problem with the connection or faulty jumper cables. A completely discharged or faulty car battery could also be the cause or it could occur with a faulty starter motor or faulty neutral safety switch.
In this guide we evaluate the main causes of a battery that does not jump. We also show you how to solve each of the problems.
Reasons why the car does not start with Jump
1. Bad connection
If the battery is fine, there may be a problem with the connection of the jumper cables or battery terminals. Look at the terminals and connectors for corrosion.
Fortunately, this problem is easy to fix. You can use baking soda and water to remove corrosion. Reconnect the battery and jumper cables and make sure everything is secure before trying to connect it again.
2. Defective jumper cables
Don’t look beyond the obvious when jumping straight to the bigger problems that may exist. If you have a set of cheap or thin jumper cables, you may miss them. You should also try to leave the battery cables connected for about 5 minutes before attempting to start, to allow the battery to charge the faulty battery.
Even if you have good equipment, cables can break over time, especially if you don’t take care of them. Try another set of cables or use a portable jumper instead. If you purchased very thin jumper cables, this could also be a problem if you are trying to start a larger engine.
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3. dead car battery
Most of the time, problems come from a completely discharged battery with a faulty cell or a short circuit, which could cause an electrical malfunction. Quick start will not work if the battery cannot be renewed.
Smaller jumper cables will not be able to supply power on their own without charging the faulty battery with the correct battery for some time, so if the battery cannot receive power it will not be enough.
You’ve probably noticed symptoms of battery drain, dimming headlights, or lengthening boot time. Your local auto parts store or repair shop will test the battery to determine if it can’t explode.
4. Defective starter
When you put the key in the ignition, the starter activates the engine. Energy is transferred from the battery to the starter motor, so it starts turning.
However, when the starter motor starts to fail, you will not be able to start the engine even if you try to jump start the battery. You will most likely hear a clicking noise indicating that the starter motor has failed.
5. Bad neutral safety switch
The neutral safety switch on automatic transmissions prevents your vehicle from starting unless the car is in park or neutral. However, when the neutral safety switch fails, your car may get a false reading causing the engine to face a no-start situation.
You can try going neutral to see if it starts with this setting. Otherwise, it may be difficult to determine whether the neutral safety switch has failed.
6. defective alternator
Although a faulty alternator doesn’t cause this problem right away, it can cause your car to stall shortly after removing the jumper cables. The battery does not work alone. The alternator is responsible for keeping it charged and keeps the vehicle’s electrical system running when the engine is running.
If the alternator fails, the battery will not recharge. No matter how much you skip it, the battery will drain again as soon as the juice runs out. The symptoms of a bad alternator are similar to those of a dead battery; many people confuse them with each other. However, you can test the alternator at your local auto parts store.
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Troubleshoot a car that won’t start
1. Let the battery charge
Before attempting to restart the car, let the jumper cables sit for a few minutes. With the right car running, the dead battery receives a small charge.
When the battery is very low, it can be difficult to restart it. The cables alone will not provide the necessary electrical power, but a few minutes should be enough.
2. Check jumper cables/connections
If the battery appears not to be charging, check the jumper cables. If the rubber coating on the cables is hot, there may be increased resistance preventing current flow. You should try using a different set of jumper cables or resort to a box.
You’ll also want to take a closer look at the battery terminals. If there are green or white chalky substances on the battery, it is corrosion. This corrosion can prevent your battery from getting the charge it needs. Remove the jumper cables and clean any corrosion. Once the terminals and connectors are clean, you can try resetting it.
3. Perform systems checks
If nothing else has worked, it’s time to start looking at major systems to see where the fault might be. There are not many major systems that can cause a no-boot situation. Although many people claim that a clogged filter or spark plug problem will make you think the battery is dead, that is not true. In both situations, the engine will continue to run, but will not start.
You can start by shifting into neutral to see if you can start the car now. If so, this indicates that the neutral safety switch has failed. Test or install a new battery to make sure it is in good condition before doing anything else. If not, you want to have the possibly faulty boot bank tested to see if that is causing your problems.
4. Seek professional help
When all else fails, you will need to seek the help of a mechanic. The diagnoses that need to be made may be beyond what you can do on your own. Have the vehicle towed to a reputable location and hope for the best.
How to start a car
There is always a chance that you are not starting the car properly. It’s always good to have a quick reminder on the proper steps to make sure your battery has the connection it needs. Here are some simple steps to follow:
- Park the two cars together, with the hoods facing each other.
- Open the covers.
- Connect one of the red jumper cable clamps to the positive terminal of the dead car battery.
- Connect the other red clamp of the jumper cables to the positive terminal of the healthy battery.
- Connect the black clamp to the negative terminal of the working car battery.
- Attach the other black clamp to some unpainted metal found on the dead car. If you connect it to the negative terminal, there may be sparks.
- Try to start the dead car. If it doesn’t start immediately, you can wait a few minutes for the battery to recharge.
- When removing cables, do so in the reverse order of installation.
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Once the car is running, it is best to let it run for at least 15 minutes. The longer it runs, the more the alternator will charge the battery. If you can, take the car out on the road for a short test drive, as higher speeds also help recharge the battery. Whatever you do, don’t turn off the car right after jumping or you could experience the same problem.