How to fix Makita battery charger problems?

Here are some common questions collection about Makita battery charger problems, I think you will find valuable if you are using Makita power tools.

When your Makita battery charger or battery is not working, one way is that returning it to the place you purchased it. Or call the salesman and he comes to your jobsite and takes care of problems. Another way is that test and fix them by yourself, so here will share you some simple but more effective ways.

How to charge Makita 18V Battery with low voltage problems

If your Makita battery wont charge due to low voltage,sample way to fix it as below step by step:
1. Jump starting the battery with a different charger like RC hobby battery charger.
2. Select Nimh not Lipo to charge. Select lowest amp and charge it for a few min.
3. Bump up amps a little.
4. Charge it a little more.
5. Bump up amps again.
6. Charge few more mins to 18V.
7. Put charger setting back to lipo now. Make sure it charges with no error.
8. Now charge with original charger.
9. Fully charged in about 15-20 min.

Video from Mr.ToolMan

How to reset Makita battery chip

There are two reasons could have caused the Makita battery chip problem as below.

One is that the temperature or cutoff or individual cell monitoring sensor in charger that dont allow the batteries to take a charge. Once the same condition is detected 3 times by the same charger it considers the batteries to be bad and refuses to accept it.It is a protection chip to prevent battery melt down.

Another is that the chip in the battery pack if drained dead or sits to long will brick the battery permanently making it unusable.

Problem is there is a lot of these batteries going to the landfill that are perfectly fine and just need the chip reset.

Frist, testing the battery cells, If one of the cells has gone to zero, the cell will need to be replaced before any further repair can be done. You may have several batteries with a faulty cell.

Once you found that the internal chip protection board has been the cause of the problem, like the fusible link being blown, a faulty internal chip etc. You can check the following question.

How to fix Makita charger due to a faulty internal chip

You can bypass the fuse when it melt down, however as you are bypassing a fuse the next time such fault occurs there will probably be irreversible damage to the electronics.

So what you have done is override the shut down chip with the chip from the other battery.

How to replace the riveted protection board? you should purchase one 18V Li-ion Battery Protect Circuit Module Board (As below image)

Video from Well Done Tips

FAQ for Makita battery charger

Makita charger lights mean

How to test a Makita battery charger

When put the battery into Makita battery charger, if the lights are not flashing, it mean that the battery or charge is likely defective, but how to judge?

First you check the voltage of your drained battery by a test multimeter. For 18volt battery if it is close to 18volts 1-2 volts less is just fine! Then there is no issue with your battery.

Or if you have another normal charger, plug the unit into a different electrical outlet. If the unit still does not receive power, it is likely defective and should be replaced.

For Makita battery compatible, plug a not full charged compatible battery into Makita charger, it is charging if the charging light change frome green to red, otherwise incompatible with the charger.

Our goal is to help everybody to save time, easy to find out a effective solution directly for Makita battery charger problems, therefore, please leave your comment on here if there is a better way, Thank you.