How many times can you jump start a car

Modern vehicles can usually be jumpstarted but it's a high risk job and mistakes can be costly. If you are in any doubt, contact us and we'll send an expert.
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Only use quality jumper leads with spike protection, or a jump start pack.
Don't attempt to jumpstart a damaged battery. You'll know it's a damaged battery if: (i) you can smell rotten egg or, (ii) if it has only been off for a short period of time before failing to restart.

The risks of jumpstarting a modern car

There are complex electronic systems in today’s cars, which is why jumpstarting a modern car can cause major damage if done incorrectly.

For example, engine control units (ECUs) constantly monitor the engine to keep its operation as efficient as possible, on board trip computers guide the driver on fuel efficiency and servicing requirements, plus airbags, cruise control, Bluetooth and other standard features of modern cars all rely on computers to function.

That's why jumpstarting can cause expensive damage to the on-board electronics of a modern car, as NRMA technical trainer Darrin Tucker explains.

“The big change is computers and it’s not as if a modern car has just one – a Mercedes-Benz S-Class from a few years ago has 64 ECUs (Electronic Control Units). Hooking up jumper leads can zap these computers,” he says.

"A five-year-old Audi was recently taken to an NRMA approved repairer with an electrical system so badly damaged by an attempted jumpstart that, in the end, it was actually cheaper to write the car off rather than repairing the damage. Well-meaning car owners can do massive damage very easily,” Darrin says.

Important steps to follow

Do not jumpstart a damaged battery. If you can spot physical damage, get a rotten egg smell, or if the vehicle fails to restart after only a very short short rest period, the battery is potentially damaged.
If you are sure the battery is not damaged, closely follow the specific instructions in the owner's handbook as different cars have different procedures.

Only use high quality jumper leads that have spike protection. Ensure the jumper leads are oriented the right way and connected in the correct sequence as described by the manufacturer. Failure to follow these critical first steps can lead to expensive repairs or a write-off.

It's safest to call an expert

NRMA patrol vehicles are equipped with top of the range surge protectors to safely revive a flat battery in a modern car, plus our experienced technicians know what risks to look for and always put safety first.

If you are in any doubt, it's safest to leave the revival of your car's flat battery to an expert. If you need help book NRMA roadside assistance or call 13 11 11 to request a patrol.

Most of us spend a significant amount of time in our cars, whether it’s commuting or running errands or simply enjoying the road. But many of us don’t know the basics of vehicle maintenance or repair. With a little do-it-yourself spirit and a few basic tips, you can learn how to do most anything on a car.

First, find the owner’s manual for your vehicle. This is a high level guide to most of the major components, complete with troubleshooting suggestions for your particular make and model.

How To Jump Start A Vehicle

Keep the following in your car at all times:

Jumper Cables: The longer, the better!
Mechanic Gloves: Disposable gloves at the very least, but heavy duty offers more protection
A Flashlight: Always handy to keep in your car!
Paper Coveralls: Protection for your clothes – paint stores usually carry these
Owner’s Manual: You can often find this in your car’s glovebox

To jump start your car, you will need to find someone with a vehicle to provide the jump to your dead battery. It is important to be safe and use sound judgment when seeking assistance from people you don’t know. Don’t accept help from anyone you don’t feel comfortable around, and be sure to phone a loved one to let them know exactly where you are and what’s going on.

Before you and your helper begin the jump-start process, here are a few words of caution:

Read your owner’s manual, first. Your manufacturer may advise against jump starting a vehicle due to sensitive electronic circuitry.
Don’t try to jump a frozen battery.
Do NOT jump a battery that is cracked or leaking. This is very dangerous. You will need to purchase a new battery at this point, so call a tow truck or a friend that can help you out.
Ensure that the battery isn’t dry. Check individual cells for fluid levels and add water accordingly. Check your owner’s manual for details and warnings.
If there is corrosion (white or greenish powdery stuff) on the battery, try to clean it off with a wire brush, aluminum foil or anything but your hand as the chemicals can be damaging to your skin. Be sure you cover your nose and mouth to avoid inhaling the dust as it is a lung irritant.
Once you begin the process of hooking the cables up NEVER allow any of the hook-up clamps to touch. Each person should hold an end of the cables and keep the two clips separate (one to each hand is a good idea).

Step-by-step Guide:

Start by protecting your clothes and your hands with protective clothing or a blanket on the ground and gloves.
Open the hood to your car. Sometimes when you “pop” the hood, you need to also release the latch. This can be found by running your fingers under the slightly open hood until you find a little lever to push on. Use the stick to prop the hood open while you work.
Locate the battery. If you aren’t sure where to find the battery, your owner’s manual should provide instructions or a picture to guide you.
Ensure that the donor car is parked close to yours and that it is turned off before you start.
On the battery there are two post “terminals”. One is positive (+), usually red and one is negative (-), usually black.
The positive terminal post (+ or red) should have a plastic cover that opens easily to expose the metal beneath. Keep in mind that when you begin to attach the cables to each component, you want it to be as solid as possible to ensure a safe and complete connection.
Take a POSITIVE (red) clamp and attach it to the dead car’s positive terminal post (+ or red). The clamps should have metal teeth that help them grip the terminal post.
Take the POSITIVE (red) clamp at the opposite end of the cables and attach it to the positive terminal post (+ or red) of the good, working battery. Their car should still be off!
Next, take the NEGATIVE (black) clamp on that end and attach to the (-) terminal of the good, working battery.
Take the final NEGATIVE (black) clamp and attach it to a non-painted metal surface on the main engine block of the car that is being jump-started (yours). A good metal surface could be a metal nut or bolt and farther away from the battery is better to allow for solid grounding.
At this point, once all of the connections have been secured, start the donor car. After a few minutes, try to start your car. If your car won’t start, then wait several more minutes and try again.
If this doesn’t work, stop. Working in reverse order, unhook each of the clamps and thank the owner of the donor car. It’s time to call for professional help.
When the dead car is started, check the battery light on the instrument panel. If it is on, this may mean that the alternator is not charging the battery and the driver should not run the vehicle very long. If this is the case, call for professional help.
If your car does start, let it run for a few minutes to help charge the battery further.
Unhook the clamps in the reverse order of how you put them on. Be sure to drive your car for about 30 minutes before stopping again so the battery can continue to charge. Otherwise, you might need another jump start.

For the true do-it-yourselfer, look into a Jump Start Box or Jump n’ Carry. These small boxes run about $150, but they can provide you with a solo jump start regardless of where you are. Be sure to read the details and your owners manual to ensure this is an option for your vehicle.

Print this article out and keep in your glove compartment for easy reference.

A dead battery is just one of the things GEICO’s Emergency Roadside Service can help you with if you get stranded. Add it to your auto insurance policy today for just pennies a day per vehicle.

Next article: How to Check Tire Pressure

What happens if I keep jump

So what about your car when jump-starting another battery? This process will put slight stress on your battery and alternator. However, in most cases, this process is harmless. A healthy battery will be unfazed by the jump-start, and your battery will recharge as you drive.

How many times should you try to jump a car?

Start the engine of the dead car. It may take more than one try, but do not try to restart it more than three or four times.

Can you damage a car by jump

Like most electronics, a power surge can cause damage to the electronic systems of a modern car. A seemingly well-meaning jumpstart can cause said power surge and impact the effectiveness of onboard computers, safety systems, damage the engine and be the result of expensive repairs.

How many times can a battery start a car?

An auto battery has a limited number of times it can start your vehicle before it needs to be replaced. Most car batteries will last between 500 and 1,000 charging cycles, which works out to a lifespan of between three and five years, depending on driving and weather conditions.