Battery’s dead, so you grab your drill, screw it in to the socket and nothing happens. Plug it into the charger. Turn it on.
Nothing. Wait. Nothing.
Frustrating? If you’re like me and own any power tools, then yes. It becomes a half-day project rather than a quick fix.
And the charger is an unseen hero of that system. You don’t think about it when it’s working. Stop using it when it’s not.
But most people assume it’s the battery. Change batteries. Buy new ones.
Toss out old. But more times than not, it’s the brick on the bench causing the issue. A cordless drill battery charger isn’t exactly cutting-edge technology, there’s no fancy diagnosing required here.
It’s pretty simple electrical sanity stuff. Do I need a multimeter? No, unless it’s for further troubleshooting so you can tell if thing is dead or alive.
So the question is: Is it the battery? Or is it the charger? Or perhaps it is the wall outlet itself.
That’s what this test isolates. It also shows why it save you money. Maybe all you needed was a new charger cable, but instead, you went out and bought another battery.
Or maybe you thought your battery was dead, but now you find that it’s at the end of its useful life. Either way, you’ve saved yourself some coin by doing this.
How To Test Cordless Drill Battery Charger
Check the Power Source First
The first variable to check is also most apparent: Power.
No it’s not silly. A dead outlet is far more common then you might imagine. Try plugging in something else (a phone charger), maybe a lamp, and see what happens.
If the lamp doesn’t turn on, your issue is upstream. Your device isn’t busted; your issue is upstream. It is the breaker box.
But before you declare your DeWalt or Milwaukee charger dead, make sure the outlet has juice. You will avoid half of your fake emergencies this way, so you won’t spend time troubleshooting hardware for no good reason. It might be because someone plugged it in wrong or flipped a breaker.
Clean Charger Contacts and Terminals
Examine physical connections next. Examine the charger contacts. Metal shavings and other crud get into charging contact slots where battery sits.
That gunk prevents contact between charger and the cell. Wipe them clean with a cotton swab soaked in rubbing alcohol or just wipe gently with a dry cloth. Also examine the battery terminals.
Any corrosion or dirt on those will prevent communication from the charger to the battery management system. This is a no-go signal. A quick cleaning of these surfaces can bring back what appeared to be a dead connection.
It is low effort with a high success rate.
Interpret Charger Indicator Lights
Next up, check the indicator lights. Codes vary by brand.
Generally, a solid green light mean that the battery is fully charged. Amber or red blinking means it’s charging. Red solid could signal a fault.
Read your manual. But if the light never comes on, there are two possibilities: either charger has a blown internal fuse or it isn’t getting any power. Or, if it’s rapidly blinking, it’s possible the charger is indicating it’s rejecting the battery.
This might be because of cell imbalance or temperature extremes. Knowing what the codes are important. That lets you know if charger is totally offline or actively attempting to do its job.
Isolate the Fault with a Known Good Battery
Isolate the issue Insert a known good battery into the charger. Does it charge like normal? If it charges normally, then your original battery is likely the problem.
The battery either has a broken internal circuit or a failed cell in it. If your known good battery doesn’t charge as well then the issue is with charger itself. It’s defective.
You can quickly isolate the issue by swapping batteries. This will let you know whether it’s an issue of storage or an issue of charging (power delivery). You need to know what is wrong before you can troubleshoot properly.
Consider Environmental Factors and Age
And don’t forget about the environment too. Extreme temps are no good for lithium-ion batteries. A cold battery charged in the garage in middle of winter will cause safety shut-offs.
Why? The charger detects the cold temperature and stops current from flowing to prevent plating. Take it inside.
Let the battery come back up to room temp. Re-try. That’s an environmental variable that gets ignored.
And it’s the reason why your charger rocks in the shop but not out on the job site. Managing temperature is part of care routine. Finally, inspect your gear for its age.
A charger will get worse with age; the internal switching components will fail eventually. Is your unit ten years old? It could be acting up.
Chargers can often be replaced cheaply versus buying a new battery. Test it if you suspect the charger and if your testing leads you there, toss it. Don’t fix it.
Even if fixed it’s just too dangerous to have one that may catch fire or give someone an electrical shock. Investing in a spare charger isn’t a bad idea. That way when main one goes kaput, no downtime.
Return to that original frustration, but use method and patience. Don’t freak out when the drill fails. Go through process.
Is it plugged in? Are the contacts clean? What’s the light say?
Try new batteries. Simple problems are usually that way. You don’t have to call someone or pay money to get them solved.
Identifying the issue saves both your wallet and your sanity. Next time the light won’t turn on, you’ll already know what to check first. Save battery from the garbage can and keep project from stalling.