When an ATV is completely dead, nothing powers on, the most likely cause is the battery.
Take the battery out and load test it, the voltage does not matter, only amps matter and the only way to measure that is with a load tester. If you don’t have a load tester, you can take the battery to any autoparts store, and they will do it.
Other causes for your ATV to have no electrical power are as follows:
- Bad battery
- Bad battery connection
- Bad grounds
- Blown fuses or bad relays
- Bad key switch
- Bad kill switch, or you forgot you left the kill switch off
- Battery installed backwards
- Bad computer
Bad Battery Is The Most Common Starting Problem
When it comes to ATVs, a bad or weak battery is the cause to most of your starting problems.
ATVs are not ridden as much as people’s cars, so the lead-acid batteries tend to die when neglected.
So the very first thing you need to check if your ATV is completely dead is the battery. As stated earlier, you must load test the battery to make sure it’s good.
And yes, your ATV needs a battery to run if it’s fuel injected, but that is not always the case if it’s carbureted.
Bad Battery Connections
If the battery checks out fine on the load test, then another cause for your ATV to have no power is a bad connection.
The wires that connect to the battery could be corroded or damage and that is why the ATV has no power. I’ve seen a positive battery wire get shorted to ground because the positive wire was rubbing on the frame.
Lastly, if you have a bad ground, as in it’s badly corroded or fallen off, then that can keep an ATV from powering on. Cleaning up your grounds and positive cable terminals can go a long way to help solve the no power issue.
Blown Fuses And Relays
Every ATV will have a fuse box located near the battery and starter relay.
It’s not uncommon for a fuse to blow, especially during a hard ride in the mud. Something got overloaded while bogging it and the fuse blew.
Check all the fuses to make sure none are blown. Sometimes the manufacturer gives you extra fuses in the fuse box, but it doesn’t hurt to carry some extra mini fuses (ad).
In the fuse box will be small black relays and if they go bad it can keep an ATV from powering on. One of those little black relays control the display and fuel pump, so if you don’t see or hear those turning on, then the relays could be bad.
You have to bench test those relays to know if they’re bad, but time is better spent just replacing them instead.
Tip: The connectors the fuses plug into can also come loose over time. If you see one sitting different from the rest, that could be your problem.
A Bad Key Switch Will Keep An ATV From Powering On
The key switch will wear out over time, especially if it’s a cut key system.
Not only does the switch wear out, but the pins and connector it plugs into wear out too.
I had an ATV with a phantom cutting out issue that no one could figure out. I took the key switch out and noticed it sat loose in the connector and one of the pins was bent and loose. Fixing the pin fixed the random cutting out issue they had, so make sure to check your pins!
Water can also get in the key switch and cause corrosion and all kinds of no-power issues for an ATV or side by side.
A Bad Kill Switch And Not Having It On
You can have two types of kill switches on an ATV, the common red flip switch on the left side and the lanyard style that attaches to you which kills the engine if you fall off.
If the kill switch is in the off position, and you put the key on, the ATV will do nothing and seem like there is no power. You’ll be amazed by how common an ATV comes in for a no power and dead issue, and it was only because the kill switch is in the off position. I’ve even had higher ups at the manufacturers make this mistake.
So make sure the ATV kill switch is in the “RUN” position.
It’s also possible the kill switch has gone bad or is corroded and that is why your ATV seems to have no power. An ATV won’t power up anything until that kill switch reads right, so if your ATV seems dead when you turn the key, give the kill switch a good glance over.
Battery Installed Backwards
While installing a battery backwards has become harder since the manufacturers make them to fit only one way, it still happens.
If you hook a battery up backwards on an ATV, it will blow a fuse and the ATV will be completely dead. Sometimes it will be more dramatic, and it will blow the computer too. It’s best you don’t hook an ATV battery up backwards!
So double check you did not hook the battery up backwards, positive goes to positive and negative goes to negative.
Bad Or Damaged Computer
A fuel injected ATV that has a bad computer will refuse to power up anything or give you any warnings.
Everything is run through the computer and if you tried everything else and the ATV still does not have any electrical power, acts like it’s dead, then it’s most likely a bad computer.
The dealership or repair shop will have the tools to test the computer, as it’s not something you can easily do yourself.