A flat battery is a royal pain in the ass and there’s never a good time to have one, that said as problems go it’s a simple fix. I’m a mechanic, you are in the right place and very shortly we’ll have this figured out.
To jumpstart an ATV you’ll need a donor battery and a set of jumper cables. Connect the cables in the following sequence:
- Positive on ATV
- Positive on Donor
- Negative on donor
- Ground on ATV
- Start engine
In this post, you’ll learn how to jump-start your ATV quickly and safely. You’ll also learn how to charge your battery, how to check your battery health, and how to check your alternator output, let’s get to it.
Jumpstarting ATV Procedure
Jumpstarting an ATV is a simple procedure every rider should know. The procedure is not without risk, batteries contain acid and vent flammable vapors. Arcing a jumper cable is enough to cause the vapors to ignite. While this is a small risk, it is possible if you fail to follow the set jumpstarting sequence set out below.
In addition, connecting the jumper cables incorrectly can damage both the donor vehicle/battery and your ATV’s electrical system, so it’s important to get this correct.
Tools we’ll need:
Donor vehicle/battery – Obviously we’ll need a donor vehicle or battery. Most vehicles run the same voltage system as your ATV, it’s known as a 12-volt system (although these systems are actually 12.65 volts). This is great news as it means we have a wide choice of vehicles we can use as a donor vehicle.
Cars, including hybrids and even EVs, are suitable as they run a 12-volt system alongside their higher voltage drive systems. Trucks, RVs, Riding mowers, and Dirt bikes, all use 12 volt systems and are perfect for a jumpstart.
To check your donor vehicle is a 12-volt system, go ahead and locate the battery and check the battery casing label, it will clearly state – 12 volt
There’s is also the option of using a jumper pack instead of a donor vehicle to boost start your ATV and we’ll cover that procedure below also.
Jumper cables – A good quality set of jumpers are important, poor quality jumpers will create resistance to the flow of power between batteries. Cheap cables are pain and in my opinion a waste of money. Cheap cables typically use cheap narrow gauge wire and poor clamps which as said make poor connections. Check out the ATV tools page to see the jumper set I recommend.
The process of jumpstarting is as follows:
- Access your ATV battery (usually under the seat)
- Check both battery terminals are clean and tight
- Park your donor vehicle close to your ATV
- Access the battery and identify the battery poles (embossed on the battery casing and/or terminal cover).
- The Positive terminal is marked by a PLUS symbol (+) and maybe color-coded RED. The Negative terminal is marked by a Minus symbol (-) and color-coded BLACK
The positive terminal connects to the fuse box and the negative terminal connects to chassis ground (Grd)
Connect the cables as follows:
- ATV battery Positive (+)
- Donor battery Positive (+)
- Donor battery negative (-)
- Ground point
A ground point (Grd) is any metal on the chassis or engine. We use the ground point instead of the negative terminal of the ATV battery as the final cable often causes a small arc (spark). The arc as said could potentially ignite battery vapors if connected close to the battery vent.
Starting your ATV
With all cables connected, go ahead and start your ATV and allow the engine to idle as normal. Avoid revving while jumper cables are connected.
A repeated clicking sound as you hit the start button means the batteries aren’t making a good connection, readjust them and try again.
If your ATV fails to start and offers a single click sound, you likely have a failed solenoid and not a flat battery, I wrote a post previously that covers starter solenoid testing and you can check it out here – ATV won’t start
Removing the jumper cables
While your ATV is idling, remove the jumper cables in reverse order to how we fitted them.
Remove 4, 3, 2, and 1.
If your battery is generally healthy, and your charging system is in good shape simply riding your bike for thirty minutes or so without using electrical consumers such as lights, etc, is enough to charge the battery.
However, if you have a weak battery, bad alternator, or parasitic drain you’ll be visiting this problem again before long. Makes sense to test your battery and charging system to make sure all is in order, and we cover exactly that below, but first I’ll cover boost starting your ATV using a jump pack.
How to Boost Start ATV with Jump Pack
Boost starting from a jump pack is similar to the jumpstarting process only a ton easier. A jump pack is a really useful tool to have, modern jump packs are small enough to fit in the glove box of a car and yet powerful enough to start a diesel truck, these little guys pack. Check out the ATV tools page to see the jump pack I recommend.
The jump pack process is as follows:
- Connect the Red Jump pack clamp to battery Positive (+)
- Connect black jump pack clamp to battery Negative (-)
- Start engine
Jump packs employ an anti arc feature which prevents the risk of igniting battery vapors, however, as an alternative you can connect a jump pack black clamp to a chassis or engine ground also.
How to Check ATV Battery Health
Checking your battery’s state of health is a two-step process. First, we’ll need to check battery voltage and then we stress the battery by running the Crank test. We run a voltage test first to check the state of battery charge because running the crank test on a partially charged battery will lead to misdiagnosis.
The tool you’ll need:
In this test, I use a voltmeter (DVOM) but you can also use a dedicated battery tester which is also capable of running a charging system test (covered below). The battery tester uses a traffic light system and is easy to use, the voltmeter is a little more work, anyhow you’ll find both tools here on the ATV tools page.
Check Battery Voltage – Let’s go ahead and check battery voltage using our voltmeter as follows:
- Place the red meter probe on battery Positive (+)
- Place the black meter probe on battery Negative (-)
- Read meter
Crank test – A battery may display full voltage (12.65 v), but that doesn’t mean the battery is good. When stressed it could fail and as you know that’s why we run the Crank test.
If your battery isn’t at least 12.5 volts, go ahead and charge it before running the crank test. To charge it you can run the engine or use a battery charger.
- Place the red meter probe on battery Positive (+)
- Place the black meter probe on battery Negative (-)
- Crank over the engine
- Read meter
What the results mean
A reading below 9.6 volts indicates a weak battery
Reading above 9.6 volts indicates the battery is good
How to Charge ATV Battery
Batteries don’t like sitting idle, they are designed to be used, charged, and discharged continuously. That’s what keeps a battery vibrant. And that’s why I recommend using a smart battery charger also known as a trickle charger when your bike is laying up for more than a week.
The smart charger is designed to monitor your battery state of charge and turn on and off as needed. Check out the ATV tools page to see the smart charger I recommend.
If your battery state of charge is very low your charger may not turn on, this is a safety feature.
To override this connect a donor battery and then connect the career as per the picture. The donor battery may be removed after 30 mins and continue to charge as required.
To charge your battery, follow these steps:
- Remove the negative terminal (helps remove any risk of electrical system damage caused by voltage spikes)
- Check the battery terminals are clean
- Attach the red battery clamp to battery positive (+)
- Attach the black battery clamp to battery Negative (-)
- Set charger to 12 volts, plug in and turn on
Charge time will depend on how low your ATV battery is, its amp rating, and the amp rating of the charger. Typically 3-4 hours.
How to Check ATV Alternator Output
This is a simple check and to nail it like a pro you’ll need either a Voltmeter or a battery/alternator tool and a helper would be useful. You’ll find both these tools on the ATV tools page here, but not the helper.
First, we’ll need to access the battery, then follow these steps:
- Start the bike and allow it idle (helper)
- Set the voltmeter to 20 v DC
- Place red meter probe on battery positive (+)
- Place the black probe on battery negative (-)
- Take the revs up to about 3000rpm (helper)
- Check the meter reading
What the results mean
A reading below 12.65 volts indicates your charging system isn’t working, further investigation is needed. Possible faulty stator, rectifier/regulator, or wiring circuit.
A reading above 13 volts and below 15.5 volts indicates your charging system is charging and working as it should.
A reading above 15.5 volts indicates your rectifier/regulator is faulty
If you suspect an intermittent charging issue, repeat the test with lights, etc turned on. A healthy system will offer the same results as per the previous test.
Common Causes of ATV Flat Battery
A flat battery happens to us all, sometimes it’s operator error and if that’s the reason you have a flat battery, consider yourself lucky, your work is done here, if not we may need to do a little detective work.
The most common reason for a flat battery is battery failure and we’ve covered battery testing above.
Other causes include the following:
Loose battery terminals – ATVs bounce about a lot, it’s not uncommon for battery terminals to come loose. Loose terminals will create resistance (obstruction to the flow of power), it stops battery power from getting to the starter motor but the reverse is true also, the charging states can’t get full voltage to the battery.
Dirty battery terminals – Leaking acid and arcing can cause a build-up of corrosion on the terminal which results in high resistance with the same results as a loose battery terminal.
A faulty rectifier/regulator – The rectifier regulator is a critical charging system component. It takes alternating voltage (AC) produced by the stator and converts it into direct current (DC) used by your ATV.
In addition, the regulator monitors and adjusts battery charging voltage which is critical for a healthy battery. A faulty rectifier/regulator commonly causes premature battery failure as it overcharges the battery.
In addition, a neglected faulty rectifier/regulator may damage the CDI box, which results in an ignition system failure and a no-start.
Short to ground – A short is common in older more experienced ATVs, loose or trapped wiring shorts off the ground (chassis or engine metal frame). The short causes a constant drain on the system.
Accessories are a common source of electrical shorts since the wiring isn’t factory fitted they tend to come to loose more often.
Failed Stator – The battery is responsible as you know for starting the engine but the stator generates all the voltage needed to run the bike and replace spent battery voltage. A faulty stator will affect battery charging and may in some cases drain the battery.
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- About the Author
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John Cunningham is a technical writer here at ATVfixed.com. He’s a Red Seal Qualified Service Technician with over twenty-five years experience. He’s worked on all types of mechanical equipment, from cars and trucks to ATVs and Dirt bikes.