The following is as comprehensive a guide on how to use a jump starter as I could compile. Although lengthy, I feel anyone attempting to jump start their car with one of these devices would do good to read through this guide at least once, to understand any possible dangers you could face, and what you can do to limit your exposure to these hazards as much as possible. The purpose of this is not to scare anyone however, and generally, starting your car with a portable jump starter is a relatively safe procedure..
Key Safety Precautions for How to Use a Jump Box
The following should always be observed when attempting to jump start any vehicle, piece of garden equipment, boat, and so on (simply referred to as vehicle from here on) with a portable jump starter:
- Ensure the jump starter is off before attempting to connect the jumper leads to the unit and the vehicle’s battery
- Check that the lights, radio, air-conditioner, etc. of the vehicle are turned off – remove the keys from the ignition entirely to be sure
- Do not allow the positive and negative clamps to contact each other or to be electrically connected in some way by a conductor of sorts
- Do not attempt to jump start your vehicle near flammable liquids or other combustibles
Explosions of Lead Acid Batteries are Possible but Rare
While most modern portable jump starters have safety systems in place to prevent any potentially hazardous situations from the incorrect use of the device, it is wise to always follow the above key points. An explosion is a real possibility, and if a lead-acid battery is involved, it goes without saying that this can really be a disastrous situation. Sparking is also a possibility if the jumper clamps contact each other or if they are connected to the vehicle while the jump starter is on and hence the warning to keep flammables clear of the area where the jump starting is going to take place should also be taken seriously.
With the above precautions in place, the main part of the guide will now be covered. The following is essentially the best-practice for jump starting your vehicle with a portable jump starter and should therefore be followed as close as possible. Alterative, and perhaps more familiar, practices are however indicated where applicable along with their possible effects on safety.
How to Use a Jump Starter
- Connect the jump cables to the portable jump starter while still in the off position. Some units have the cables permanently attached and so this step can be ignored in these cases.
Next, still with the jump starter and vehicle completely off, connect the positive (red) jumper clamp to the positive terminal of the vehicle’s battery and the negative (black) clamp to a stable point on the vehicle’s chassis. Be sure the clamps are solidly connected so that when the car starts, they’re not shaken loose, possibly leading to the cables touching other and shorting the jump starter. Connecting the negative jumper clamp to the negative terminal on the vehicle’s battery is perhaps a more common practice, and for most situations, will be fine. The negative terminal on the battery of essentially all cars, SUVs and trucks also serves as ground for the battery by being connected to the chassis of the vehicle. Therefore, connecting to the chassis of the car is virtually the same as connecting to the negative terminal of the battery. The reason for preferably connecting to the chassis, is that the vehicle’s battery could potentially be giving off hydrogen gas. Although quite unlikely, especially on modern car batteries, a spark from connection of both jumper cables to the battery terminals could cause a fire or explosion. The chances of this are slim, but this is the reason why best-practice would dictate connecting the negative cable to the vehicle’s metal frame.
- With the jumper cables now firmly connected to the vehicle’s battery, the jump starter can now be turned on.
- Next, the ignition of the car can be turned on and an attempt made to start the car. If the motor does not immediately turn-over, do not crank the engine for more than about 5 seconds. The jump starter is forced to deliver its maximum current while attempting to start your engine, and it is only designed to do so in short bursts. Pushing the jump starter to crank your engine for longer periods of time can cause overheating and seriously damage the battery of the device. Allow a good 2-3 minutes between 5-second attempts to allow the battery bank of the jump starter to cool and also for the voltage to recover. This will ensure it can deliver its peak current again when trying to crank the engine and of course ensure maximum life out of your jump starter.
- After the engine has started (if you can’t get it going after four or five tries, refer to the troubleshoot below), the first thing to do is switch the jump starter off. Then remove the negative jumper cable, followed by the positive and then safely pack your jump starter away.
- Then, it is a good idea to recharge the jump starter as soon as you can – immediately would be best (allowing the unit to cool for a few minutes first though) – even if there is still plenty of charge left in the device. Batteries in general, even the modern lithium-ion batteries found in a lot of the compact jump starters today, do not like to be discharged too deeply, and the maximum life will actually be obtained if they can be kept as close to fully charged as often as possible.
- Another good idea is to then have your vehicle battery checked if possible to see if any significant damage has been done by it being discharged so low that it couldn’t crank the engine. Most battery centres will do this for free and it takes only a few minutes. They’ll be able to tell you if a new battery is necessary and roughly how long your battery will probably still last.
In the event that you can’t get the engine turned over with your jump starter, a possible cause for this is that the jumper clamps are not making a good enough connection with the battery terminals. In this case, TURN THE JUMP STARTER OFF, then try twisting the clamps around the terminals to improve their connection; or if the negative clamp is connected to the chassis, try another point on the frame. Then, turn the jump starter back on and try starting the vehicle again as outlined in step 4 above. If the engine still does not start after four or five more tries, stop trying, and as disappointing and frustrating as it may be, accept that the battery is just too far gone. There are several possibilities for this, including: the battery could be catastrophically damaged internally, causing an internal short; the electrodes which form the cells of the battery could be too far corroded (or sulphated on lead-acid batteries); the electrical system of the vehicle may be damaged. The best would then be to charge your phone with your jump starter and call for assistance, or have your car towed to your nearest service station.
Get the Best From Your Portable Jump Starter
There you have it, JumpStarterExpert’s complete guide to jump starting your car with a portable jump starter. Hopefully this will serve as a valuable reference for anyone who may be struggling to get their car going with one of these devices, providing alternative strategies and a means to troubleshoot any potential issues with the way they are attempting to jump start their vehicle. Remember that poor maintenance of your vehicle’s battery and of your jump starter will only reduce your success, so be sure to have your battery checked regularly (every three months) and to keep your jump starter charged up so it’s ready for the next time you need it. As always, keep safe, and I wish you all the best when jump starting your vehicle.