If you are having trouble with your Milwaukee battery not charging, don’t worry you’re not alone. 

As with all batteries, Milwaukee batteries often go through issues that do not allow them to charge properly. Lucky for you, there are 7 simple things to try before you go out and get a new battery. 

Milwaukee Battery Not Charging

Make sure outlet you are using is working

If your Milwaukee battery isn’t charging, the easy fix is to ensure the charger’s plugged into a functioning outlet. Plug a different device into the outlet and make sure it’s working. If the outlet’s defective, try a different outlet and see if charger lights come on when battery is plugged in. 

This sounds incredibly simple, but often times it can be the case. It could be that a fuse was blown or the outlet is damaged. Do not overlook this step, it can save some time and effort.

If the outlet is not working, it will not provide power to the charger, and therefore, the battery will be unable to charge. So check the outlet by plugging in another device such as a phone charger to ensure you are getting power.

So you determined the outlet you are using does in fact work, however, the battery is still not charging. Luckily, we have other ways to fix the problem! 

Make sure the charger is working: Try another battery

While the charger is plugged in, try a different Milwaukee battery. This will quickly determine if the problems with the particular battery or if the charger is not working. 

When you plug in a different battery, if the lights on the charger appear, this tells you that the charger is working. So now you know the issue is with the battery. 

If using a different battery and you still don’t get indicator lights on the charger, this means the charger is the issue. It is rare but you also could have two faulty batteries. 

If the issue is with the charger, I recommend you reach out to Milwaukee as most equipment comes with a 1-3 year warranty.

You determined that it is indeed an issue with the battery and not the charger, then continue on to the next fix. 

Press the button on the battery when plugging in

It’s crucial that you press the two red buttons on the battery, as it slides down the charger. This ensures there’s an appropriate connection between the battery and charger terminals. You will still get a solid green light on charger if this is done incorrectly, however, the battery isn’t charging. 

As seen in the picture, there are two red buttons on the sides of the battery. These are the same buttons you press to remove the battery from a tool. It is essential that you press this button when sliding the battery down the charger. If it is done right, you should hear an audible click, this will indicate that the battery is on properly. 

If this is not done properly, then the battery will just be resting on the charger. When this happens it will give the appearance that the battery is fully charged. There will be a solid GREEN light showing on the charger (just as appears when it is indeed fully charged). 

What happens in this scenario is that you think the battery is fully charged, so you go and use it, but it only lasts a couple minutes. This is a quick indication that the battery has not been properly placed on the charger. 

Just a reminder, if the battery is not fully charged, you should see a solid red light on the charger when the battery is plugged in. 

Below is a guide to the charging lights that you will see on a Milwaukee charger: 

• Solid RED light: Battery is charging
• Solid GREEN light: Battery is fully charged
• Blinking RED light: battery is too hot or too cold
• Blinking RED and GREEN lights (simultaneously): Damaged or faulty battery

If you are getting an audible click when placing the battery on the charger, and you find the battery is still not charging, don’t panic. We have a few more fixes to try. 

Unplug the charger and wait 10 seconds

If you plug the battery in and get a flashing red and green LED light this is a quick and easy way to reset the charger.

First you must remove the battery. Often times when the battery is removed the lights will continue to flash. Milwaukee then recommends unplugging the charger from the power source and wait until the lights stop flashing. Usually this takes about 7-10 seconds.

Once the lights stop flashing, re-plug the charger cord into the power source. Then you can reinsert the battery pack (make sure you hear an audible CLICK). If the red light comes on and stays solid, then the battery is charging.

If the red and green lights continue to flash, move on to the next step!

Clean the connections of dirt and debris

If there is dirt on the terminals of the battery and or charger, this will not allow for a good connection. This interruption in the connection will not allow the battery to charge. 

The terminals seen above, on both the battery and charger must be clean and free of debris in order to maintain a solid connection. 

Often the debris will be visible (dust, corrosion, dirt, etc). However sometimes they may appear clean but in fact there is enough “gunk” in there to disrupt the connection. 

It is important, if the terminals appear clean and nothing is standing out, “STILL DO NOT SKIP THIS STEP”. There is absolutely no harm in cleaning out the terminals and it may solve the issue. 

The terminals on the charger are bigger, and in my experience much easier to clean. I use a Q-tip and some rubbing alcohol. You want to make sure you hit both sides of the terminal with the Q-tip.

The terminals on the battery are much smaller and harder to get into. For this I have found either an envelope or sand paper folded over does the trick. You want to use something that will be firm enough to not crinkle or loose its shape when you slide it in the slits. I have also found you can dip the sandpaper or envelope in rubbing alcohol to enhance the clean. 

Often if using a white material you will actually see the black soot coming off as you stick it in the slits. 

Once you have cleaned all the terminals (on the charger and battery), try plugging the battery back in. You should see a solid red light on the charger, if the battery is charging.

This is a quick and easy fix that is good to get in the habit of doing every couple of months. No matter where you store the battery/charger, debris will build up. It is important to keep the ports clean in order to maintain a quality connection. 

Slowly charge the battery for 2-3 minutes at a time

If a battery gets below a certain voltage, it can become flat. If that is the case, you can try charging the battery for 2-3 minutes at a time for a total of about 30 minutes. You can think of this as a way to jump start your battery. 

Think of a flat battery as being fully dead. When this happens it cannot hold a charge so by putting it on the charger for shorter bursts will help kick start it back to life. Usually after about 30 minutes of these short bursts, the battery will have enough juice that it can now be fully charged. Again a solid red light on the charger will indicate if this fixed the issue.

If these 6 fixes have not worked to get your Milwaukee battery charging, there is one final thing you can try before contacting Milwaukee. 

Use speaker wire to connect dead battery to a healthy battery

If you have tried all the other steps and the battery will still not charge. Then you can try and kick start the battery with some speaker wire. 

In older Milwaukee batteries (that do not have an indicator light) it can be difficult to determine if a battery is fully dead. The best indicator is if you put the battery on a tool and you get absolutely no power. With newer Milwaukee batteries that have the indicator light on the front. You can determine a battery is dead if you press the indicator button and no lights come on. 

In this case a couple things may have happened. As described above, the battery may have gone flat. Or the battery was so depleted that it went into sleep mode. If this happens, the battery will not even register when placed on the charger. So we need to give it a jump start, just like a dead car battery. 

In order to perform this technique, you need to have a fully functioning and charged Milwaukee battery. 

It is important to note, that on every Milwaukee battery there is a positive side labeled “+”, and a negative side labeled “-“.

Place the two batteries next to each other. Take some speaker wire with the covering removed at the ends so the wire is exposed. Connect the “positive” terminal on the healthy battery to the “positive” terminal on the dead battery (+ terminal). Then take a another piece of wire and connect the “negative” terminal on the healthy battery to the “negative” terminal on the dead battery (- terminal). Make sure that you stick the exposed wire deep in the terminal so it maintains contact with the metal. 

Hold the wires in place for about 15 minutes. That should provide enough “juice” from the healthy battery to jump start the dead battery. Then disconnect the wires. Now try placing the dead battery on the charger. It should indicate that a charge is in progress (solid red light). 

Here is a video that shows this process.

There are a number of different reasons why your Milwaukee battery may not be charging. Luckily, you can try these 7 proven fixes to get the battery charged again. 

Conclusion

• Make sure outlet you are using is working
• Make sure the charger is working
• Ensure you are putting the battery on the charger properly
• Unplug the charger and wait 10 seconds
• Clean the battery and charger terminals of dirt and debri
• Slowly charge the battery for 2-3 minutes at a time
• Jump start the dead battery using speaker wire and healthy battery

If you have tried all of these fixes and the battery is still not charging, you should go ahead and contact Milwaukee at: 1-800-729-3878. 

It is also good to know, most Milwaukee products come with a 3 year warranty. You can look up more info on Milwaukees warranty policy for further information. 

Were you able to get your Milwaukee battery charged again? If so, let me know in the comments section.