How to get going again if your battery has let you down
As car owners and regular road users, many of us worry about a breakdown that will leave us stranded. Similarly, finding out that your car battery is flat and you can't get home can cause great anxiety; that awful feeling you get when you turn the key and nothing happens or the unsettling, dull click beneath from the starter under the hood need not signal the end of your journey. There are still a few ways to reinvigorate the battery and get back on your way, so knowing how to jump start your car is a vital life skill.
However, this is not something you can do alone since you need to have access to another car's battery. You could call your roadside assistance provider, but failing that, your best bet would be a friend or a generous stranger pulling over to help you out. Here, your options include push starting (if you drive a manual) or jump starting. With regard to the latter, you will need to ensure you have the correct equipment on hand.
Jump starting a car is essentially just directing power from an external source to the internal battery. This is most often necessary after a prolonged stint of inactivity or in particularly cold weather conditions. The most common solution to this is using jump leads to connect your car's battery to another. Alternately, you could also get power from a portable car battery pack, which negates the need to rely on another person. Though this may seem like a quick hack, it will cost you around $400.
In either case, you will be jump starting the car with leads. This device comprises a pair of cables wrapped in thick rubber and tipped with crocodile clips. This allows them to transmit electricity without the risk of shocking the user. It is highly advised that you keep a set in the trunk, as you cannot rely on friends or helpful strangers to have their own.
The most prepared among us probably own a portable battery charger, since it is a handy little tool. Whether at home or out on the road, it can be used in lieu of a jump start to get your dead battery going again.
Using jump leads is actually quite simple, but the fear of getting shocked or making a mistake overcomplicates things. Once you get the hang of things, though, you can jump start your battery quickly and easily. Follow these steps on how to attach and use jump leads:
While many diesel engine vehicles sold in the USA differ from gas-fed ones in that they sometimes have two batteries instead of one, this doesn't significantly change how to start a car with a dead battery. So long as it has a manual transmission, you can still bump start a diesel without any fuss, while you can jump start a diesel by connecting the leads to either of the two batteries, since they are connected in parallel.
You should start with the red cable first, connecting to the dead battery and then the live one on the positive terminal. Afterwards, you will do the same with the black cable, but connecting to the negative terminals instead.
If your battery is completely dead, the only reliable way to get the car started is via a jump, although you may have some luck trying to bump start the car. The best plan is to connect your leads to a working battery - how long it will take depends on the starting charge, but you can expect to wait between five to ten minutes.
A car breakdown is not considered an emergency situation. As such, it would not be appropriate to call 911 in the US. Instead, you should call your roadside assistance provider. Alternatively, you could try to get in touch with a towing service, but these days, you can actually call an Uber instead, it will be a lot cheaper. Roadside assistance should come with their own car battery jump leads, but it doesn't hurt to have your own, just in case.
It is possible to jump start the battery in an automatic vehicle, and it does not require deviating from the steps already explained. However, it is impossible to bump start an auto due to the open clutch setup.
If you are certain you have given the process enough time to properly charge the "dead" battery to the point that it should be able to start but it is still not working, then chances are that your battery is no longer viable. In this situation, you don't have much choice but to replace it.