Hooked ATV Battery up Backwards – What to Do?

If you accidentally hooked your ATV battery up backwards, do not panic. Disconnect the battery and let’s go over what you need to do to fix your ATV.

The good news, it’s usually something simple.

The Good News

The good news is that many of your modern and even older model ATVs have a fail-safe for this exact situation.

You most likely only fried a fuse.

Remove the battery entirely from the ATV to get a better idea of this fuses location.

This fuse is often in line with the ATV’s battery cable, check this fuse to make sure it’s not blown. The fuse is usually either a 15 amp blue fuse or a 30 amp green fuse.

If you can’t find this fuse, then it’s tucked inside your fuse box. This is the most common location for higher cc ATVs. Pull out each fuse to see if they’re blown or if you have a multi-meter check for continuity of the terminals. This video below will show you how to do that.

Fuses Are Okay, What’s Next?

If the fuses are okay, go ahead and put your battery on a battery charger. Usually, when you put an ATV battery in backwards, the fail-safes create a short to ground and drains the battery.

This short can damage older batteries and drain new ones. You’ll want to see if the battery can take a charge before putting it back in. Many battery chargers will also test the battery to make sure it’s okay. If the battery does not charge, you’ll need a new one.

Battery Is Fine

If the battery charges and seems fine you’ll want to put the battery back in the ATV but this time connecting it correctly.

You’ll want to do the positive terminal first and then the negative.

The best way to remember this is if you’re adding the battery you do the positive (+) first. If you’re removing the battery, you remove the negative or subtract (-) the battery from the ATV. This order is critical and minimize future electrical trouble.

If you replaced the fuse and reconnected the battery in most cases, that is all you need to do. The ATV should power on, and you can go ride.

If you turn the key on and nothing happens then read on.

ATV Won’t Turn On

If replacing the fuse and charging the battery doesn’t work…

Get a new battery.

I know it sounds crazy, but batteries are the most grumpy things in the world. The battery charger will say it charged fine, but sometimes batteries lie. If the battery was old or already weak putting the battery on backwards could have been the final straw for it even if the battery charger said it charged fine.

Take the battery to an auto parts store and have them load test it. Load testing is the only way to determine if a battery is good or bad. In most cases, it’s the battery causing you issues, and you’ll need to replace it.

If the battery load test fine then things only get worse from here.

Fried Something

If the battery is fine, fuses have been replaced, but you still have a dead ATV then you’ve fried something.

Hopefully, it’s only a relay in your fuse box and not the ECM or ignition system.

You’ll know you fried something because you can smell electrical smoke or may even see smoke. If this is you, then you need to take it in to be worked on. Even if replacing the fuse fixes the issue you could have destroyed something else or something is about to break. The last thing you want to happen is to have created a phantom electrical problem that finally catches up with you on a ride.

Sorry to be the bearer of bad news but if you’ve come this far it’s more then likely the ECM is fried. This really sucks if you have a Can-Am with a DESS key because you’ll have to take it to the dealer to get reprogrammed.

At this point, it’s best to take it to your local repair shop and let them fix it.

Tips For Not Hooking The Battery Up Backwards?

I see this mostly happen when people try to jump off an ATV, and they get the leads backwards. For one thing, you should not be jumping an ATV off with a car. If you’re using a jump pack, the only thing you can do is make sure to hook it up correctly.

Looking twice can save you so much trouble.

I ride with some guys who take a red or silver sharpie to the battery to remind them of the positive side. I’m not a fan of this as it will just get covered in dust and mud eventually.

One thing I have noticed is that you can avoid a lot of this by not buying the cheap batteries. I’ve seen way too many cheap batteries have the terminals in a way that doesn’t match the manufacturer supplied battery setup. I know the OEM batteries are more expensive, but I’ve found when taken care of correctly they last longer then the cheap Super Store batteries and you’re less likely to screw up the install.