20 Most Recent Makita Tools 18V 1/2" Lxt Lithium - Ion Hammer Driver - Drill Kit - BHP451 Questions & Answers

Unfortunately, Makita’s li-ion battery packs have a design flaw. After having the same problem with my two batteries, I took it apart and saw the problem immediately. You see each battery pack has ten li-ion battery cells and a circuit board with a memory chip witch holds the charging history of the battery pack. But that memory chip constantly draws power from 2 of the 10 batteries. The current it draws is very small but if you consider it over 8 month or more, the power drain becomes very significant. You end up with a battery pack with 8 still fully charged battery cells and 2 drained battery cells. When you put this battery pack in the charger, it detects weak battery cells, assumes they are defective and refuses to charge. To avoid this problem you should charge your battery pack often, even if you haven't used it, every two months should be ok.
I suspect that Makita doesn’t make these battery packs, they make power tools, good ones too. Buy Makita should definitely have a few words with their supplier before they become a liability!

Makita Tools 18V... • Answered on Feb 03, 2021

Go to MAKITA.com and under the heading Factory and authorized service centers type in your model number and you should be able to download a manual. I had a couple of these when I worked for Makita and when running they are great. Good Luck. Dave

Makita Tools 18V... • Answered on Jul 08, 2020

Do not keep her on cold place. sorry but you have to buy new one again :/ take a look on amazon or something: Amazon com Makita 18 battery

Makita Tools 18V... • Answered on Mar 18, 2019

If you haven't fixed it yet here is the way that I have used to solve this problem. Spray some WD-40 on the inside of the chuck. Place a shop rag around the chuck and CAREFULLY grip with a pair of channel lock pliers set the drill rotation so that it will extend the jaws and SLOWLY depress the trigger. It should move. Let me know if I can help more. When trying this DO NOT SQUEEZE TRIGGER to full RPM.

Makita Tools 18V... • Answered on May 16, 2018

hi it sound that the generator has blown the rectify on the charger unit

Makita Tools 18V... • Answered on Jan 23, 2018

free up the stuck brush and it should work again

Makita Tools 18V... • Answered on Dec 18, 2017

Mix a little JB weld stick anything to head of stuck bit. let harden and pull the sucker out.

Makita Tools 18V... • Answered on May 16, 2017

if you trap the chuck in a bench vice or alike and then use the drill in reverse in short bursts until it loosens a good spray with wd40 will also aid the situation

Makita Tools 18V... • Answered on Apr 17, 2017

check the position of the forward/reverse switch as if it is not properly positioned the current doesn't know which way to spin the motor check that switch for loose wire or being faulty

Makita Tools 18V... • Answered on Jun 13, 2015

I did get an educated electronics eng. tell me li ion batteries 4handtools,are manufactured to only be recharged a set number of times,to avoid tool damage.

Makita Tools 18V... • Answered on May 13, 2015

Makita has a 1 year warranty on Lithium Ion Batteries. Contact your local service center ASAP http://www.makita.com/en-us/Modules/Service/ServiceCenters.aspx or call them at 1-800-4-Makita

Makita Tools 18V... • Answered on Mar 18, 2015

i bought a new makita cordless drill in united states of america brought it home to the republic of ireland got a 110 adopter to recharge the battery but it will not hold the charge would it be the flight home have wiped the batterys what do i do?

Makita Tools 18V... • Answered on Jan 20, 2015

I also have the same dilemma,and of course,it occured 1MONTH after 1year warranty expired.I know my batts r still fine,as I recharge em on my foremans kit. My charger plays a tune,then just blinks red,green....etc.Wish I had some tips to try,from an electronics brain-type person.......lol,good luck::

Makita Tools 18V... • Answered on Dec 09, 2014

Try charging the battery with a car charger set on low (2 amps max) or a wall transformer from a phone or some such with a 12v output. (make sure it is 12vdc not 12vac)   You will need to know which of the charger wires is pos and neg, be careful not to short the battery as this will blow the fusible link. Connect + to + using jumper clips or stiff wire jammed into the battery contacts. Once you get the battery over 10-12 volts the charger will normally accept the battery. You can jump one good battery to the bad to do this, but in all cases watch out that the wires do not get hot, as this is a BAD sign, often a minute or two will be enough. Of course you may have a dodgy charger, they are not robust at all.  The fans also ****, noisy and sometimes they quit, causing the charger to quit too
Matt  Giantglobes.com
For other battery issues see below
If you have been a bad boy and managed to short the battery by using it for non-proscribed purposes, the fusible link will blow (kind of like a fuse) To fix it, open up the battery (use a Torx 10 security bit, or a small flathead in a pinch) On the battery connection nearest the spring-loaded white catch there is a small bridge of metal with a hole in the center. If this is melted you can solder it back together by sanding the two pieces and putting a glob of solder on them. This will void your warranty (duh!) and remove the battery's fuse protection, but it WILL work again. If the link is intact and nothing else is obviously wrong, you almost certainly have a bad cell. I recommend pulling out the bad cell ( it will be the one that does not read between 2.5 - 4 vdc) and replacing it with one from another dud battery- this requires some fudging and re-soldering. Or do what I did, pull the cell, toss the electronics and the short pink wire, add a cigarette lighter socket and voila! you have a portable power supply giving around 14 volts. Charge it up by wiring two cigarette lighter male ends together (check polarity , + to + and - to -) and plug it into your car, but only while it is running or you will be charging your car battery with it! Hope that helps.
Matt Binns GiantGlobes.com

Makita Tools 18V... • Answered on Jul 06, 2014

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