ATV Winch Draining the Battery – What Is Normal and Not?

ATV winches are power-hungry little beasts that will drain your battery like no other accessory. But how much battery-drain is normal, and what may be the cause if the winch seems to be killing the battery faster than usual? This is the topic for today’s post.

How much battery-drain from using an ATV winch is normal?

It’s not uncommon that ATV owners are surprised by how fast their new electric winch is draining the battery. Even when everything is working as it’s supposed to, the battery-drain from normal winching may be of such a rate that it raises a suspicion that something is not right.

A couple of really long and hard pulls or 20-30 seconds of continuous pulling may be enough to drain the battery to such a level that it no longer has enough power to start the bike. 

ATV winches draw a lot of power when they are under full load. Much more so than the ATV’s own charging system can provide, which is typically only around 25 amps. 

Related: How an ATV charge it’s battery.

Here are some typical amp draws for different sizes of ATV winches. Please note that factors as pulling speed and motor efficiency come into play here. These numbers are for reference only.

As a comparison, the starter motor of a car draws 200-300A as well. That is a lot!

With no load on the winch cable, you should be able to run the winch all day. The ATVs stator will be able to maintain the battery’s state of charge. 

But when the winch is pulling near or at full capacity, it has to draw most of the electricity directly from the battery. 

When winching several hard pulls over a short period, the ATVs charging system’s power contribution is practically negligible. 

Some recommend using the batteries Ah rating to calculate how long you can winch under full load. In theory, a 14Ah battery should be able to provide 200A for 4.2 minutes. 

For high amp draw applications such as winching, I find it more relevant to look at the battery’s CCA rating (cold cranking amps).

The CCA rating is an industry-standard that tells you how many amps (A) the battery can provide for 30 seconds, at a temperature of zero degrees Fahrenheit, while maintaining a voltage of at least 7.2V. 

The battery in my Polaris Sportsman has a CCA rating of 320A. This tells me that the battery should have no problems with 30 seconds of full capacity winching (200A draw on my 3500lb winch). It will most likely even be able to handle up to one full minute or maybe even more. 

The CCA rating also indicates that this battery size can provide such a high amp draw created by an ATV winch at full power only for shorter periods. 

Many factors come into play when determining at what rate a normally functioning and properly installed ATV winch will drain the battery. 

• What size winch you have. A bigger capacity winch has a bigger electric motor, which can pull harder and draw more power than a smaller winch. Therefore, a bigger winch can drain the battery faster than a smaller winch.
• How hard the winch is pulling. Any size winch will draw more power as it pulls harder. Respooling the cable after you’re finished winching requires almost no power than when the winch is working at full capacity.
• How long the winch is activated. A 20-second winching session draws approximately twice as much power as a 10-second session. 
• How long are the breaks? The ATVs own charging system will charge the battery back up as long as it’s given enough time. Continuous winching or just a few minutes of riding between each time the winch is being used will not be enough to provide a sufficient charge. 
• Battery capacity: A higher capacity battery will allow for longer winching before the voltage drops too low. Warn recommends that you use a minimum of 12 Ah battery to power their 2500lb winch.
• The battery’s state of charge. A fully charged battery will last longer than a battery that is not. 
• Outside temperature: Batteries are not as effective in sub-zero temperatures. 

How to know when the battery drain is faster than it should be?

If you find that the battery drains to a point where it needs an external charging from just a few low-load pulls, or even when not using the winch at all, you know that something is not right. 

If so, you may want to do some troubleshooting to make sure everything is set up correctly and in proper working condition. 

At the end of this post, you will find a section for troubleshooting the most common causes for a battery that is draining much faster than it should. 

Often you will find that the issue is not caused by a winch that draws too much power but that the ATV is not providing enough.

How can you prevent the winch from prematurely draining the battery?

Here are some tips to prevent premature battery drain from winching. It’s recommended that you go through all of these tips before diving into further troubleshooting.

Make sure the battery is fully charged

Because ATV batteries, in general, are of relatively low capacity, it is important to make sure your battery is fully charged. This enables more winching before the battery drains too much. 

Use a battery tender to top off the battery when not in use

If you use your winch for tasks such as plowing, you may consume so much power that the bike’s built-in charging system cannot keep up. If you’re not doing much riding between each plowing session, your best bet is to charge the battery using an external charger. 

I recommend getting a smart charger that includes leads that can be permanently installed to the battery. The other end of the leads features a quick-connect plug that hooks up to the charger. This makes it less of a hassle to keep the battery fully charged at all times. 

Free spool when pulling out

There is no need to engage the winch motor to unspool the winch cable.

Tips for reduced battery drain when plowing

Plowing is where most ATV owners run into issues with the battery draining faster than the ATVs charging system can keep up. 

You typically start the ATV, use the winch intensively for 10-20 minutes before letting the ATV sit until the next time it snows. This means a lot of winching and little charging time.

Follow these guidelines to minimize battery drain when plowing:

• Always plow in low gear. This will allow the engine to run at a higher RPM, where the ATV’s own charging system can provide an optimal charge. Note that there is no additional benefit of revving your ATV too high. 
• Turn off hand-warmers and any lights you do not need. Hand warmers draw more power than you may think.
• Replace your halogen bulbs with LED to save additional energy. 
• Make sure the plow is moving freely. Lower the plow to the ground and try lifting it by hand. If there is any drag or binding, the winch will have to pull with a greater force, which draws more power from the battery. 

Use a snatch block

By using a snatch block, you effectively reduce how hard the winch has to pull by half. The winching time will be longer, but the wing will operate in a range where the motor is working more efficiently, reducing overall power consumption.

Consider installing a second, auxiliary battery

If you often find yourself using the winch so much that the ATVs OEM battery can’t keep up, you may consider installing a second battery to run your winch. 

You will still have to charge the second battery manually, but you will be able to use the winch much more without any risk of draining your ATV’s primary battery.

Use a battery isolator to make sure the winch is not drawing power from your primary battery.

Consider installing a high capacity battery

A range of manufacturers offers high capacity batteries that will replace your OEM battery. If your old battery is getting old, this may be a good option for you. 

Consider installing a deep cycle battery

Discharging a standard battery below 11.5V may cause permanent damage to the battery. 

A deep cycle battery such as a PC680 style of battery is designed to handle deep discharges caused by extensive winching sessions time after time without taking any damage. 

Troubleshooting an ATV winch that seems to be draining the battery too fast

Here are the most common issues to look into if your ATV winch is draining the battery faster than it should.

Make sure the battery is healthy

Batteries lose some of their capacity over time due to internal sulfation or a bad cell. Your battery may have enough capacity to start the ATV but not enough to power a power-hungry winch. 

This is how you test if your battery is ok:

1. Charge the battery to a full charge.
2. Let the battery sit for a couple of hours to relieve itself of any surface charge left from the charging process.
3. Use a multimeter or voltmeter to read your battery voltage. You should get a reading of at least 12.4 to 12.6V. Any lower reading means the battery is bad. Note that the battery may still be bad even if you get a reading between 12.4 and 12.6V.
4. Next, you need to do a so-called load test to see if the battery can drive a load. There are several ways to do a load test:
   • Best: Disconnect your fully charged battery and take it to your local auto supply store. They will likely have professional tools to test your battery. 
   • Better: You can buy a battery load tester for 20 – 40 dollars at most auto supply stores. They are great for keeping track of the battery health in all of my vehicles. 
   • Good: DIY load-test: Set your multimeter to DC voltage. The red lead goes to the positive battery terminal, while the black lead goes to ground. Observe the voltage reading while you activate the starter. The starter draws a high current from the battery in a short amount of time. The voltage should never drop below 11.5V. If it does, your battery is bad and needs replacing. 

Related: How to Test an ATV or UTV Battery. Good, Reduced, or Bad?

Make sure the winch is wired correctly

Your winch came with a specific wiring diagram. Any deviation from the specified wiring may cause battery drain, even when the winch is not being used. 

One common mistake is to connect the rocker switch directly to the battery instead of to switched power as instructed by most winch manuals. 

Make sure the rocker switch is not defective or corroded

The rocker switch is a weak point on any ATV winch install. It may be corroded, full of dirt, or possibly faulty. 

Troubleshooting a defective rocker switch is not always easy. Start by using a hairdryer to make sure it is dried out completely, then clean it with a good dose of anti-corrosive electric cleaner, such as WD40.

Make sure the wiring is not damaged causing a direct short to ground

Visually inspect the wiring going from the battery to the solenoid/contactor and from the solenoid/contactor to the winch. 

The winch power wire is usually not protected by fuses or breakers due to the high amp-draw of up to 300A. Any damages to the wiring may cause a short to ground. 

Each time you activate the winch will be like shorting the battery to ground. This will draw a tremendous amount of power and will drain the battery in no time. 

Make sure all connections are clean and tightened properly

If your battery connectors are loose or corroded, the ATV may not be able to charge your battery properly. And if your winch power cable connectors are corroded or dirty, you may experience power drain through shorts.

Make sure the solenoid is clean and not packed with ice

If the solenoid is packed with mud or ice, it may create a short, causing power to go to ground. 

Disconnect the battery and remove the rubber boot covering the solenoid. Reassemble everything after cleaning both the solenoid and all terminals.

Make sure the ATVs charging system is working properly

When the ATVs charging system is not working properly, it won’t keep the battery charged. Every time you use the winch, it will drain the battery while no charging is taking place. 

After just 10-20 minutes of riding and some winching, even a fully charged battery may drain so much that the ATV will stall.

The most common issue is a stator that does not provide a charge or a voltage regulator that is not working. Please refer to this post on how to test if your ATVs charging system is working or not. 

Make sure any wireless controllers are turned off and are not draining the battery

Some wireless remotes keep searching for a signal even when the bike is not running. This will cause the battery to drain over time. Turn off the remote if it has an on/off switch. 

Also, some wireless transmitters do not handle moisture very well. Try replacing the wireless remote with a wired rocker switch to see if this helps. 

Make sure the winch motor is not causing a parasitic draw

In the unlikely event there is an internal issue with your winch motor, it may cause an electric draw even when the winch is not in use. You can test this with a multimeter.

• Set the multimeter to read DC amps. Use the highest scale, usually 10A, and make sure the leads are in the correct ports. (COM and A).
• Disconnect the positive terminal from the winch. 
• Connect the red lead to the positive cable and the black lead to the positive terminal so that the meter is connected in series with the positive terminal and the winch. 
• Do NOT try to run the winch. You should get a reading of ZERO.
• Switch your meter to mA. You should still get a reading of ZERO. 
• Any other reading than zero means an internal issue is causing the winch to draw power even when not in use. Such a problem needs to be addressed by a professional.

Measure how many amps your winch draws

If you have a clamp-style multimeter, you can measure how many amps the winch draws both under no load and with a full load. If you get a reading over 20A when running no load, the winch motor may be dragging or something wrong that prevents the winch from turning freely.