Here at Ionic Industries we regularly receive customer support enquiries asking for help getting our replacement batteries working in their electric toothbrushes. We have outlined our top trouble-shooting tips on a dedicated Customer Support page so if you’re having trouble getting your toothbrush back up and running take a look then post any questions and queries below.
Happy Repairing!
I don’t think I had any problem with the battery replacement procedure of my Oral B Professional Care Type 3756. I fitted the larger battery and found the instructions excellent and quite straight forward. After charging overnight, all indications were as normal and the toothbrush operated well if a little slow. Although recharging was not indicated, I put it back on charge after use. After only one further use the flashing red “charge required”light indicated recharging was required again. After leaving it charging overnight, the green “charging” light is flashing rapidly. If I remove the toothbrush from the charger, the red “charge required” light flashes rapidly. Worst of all, the motor now fails to run. Have you any advice please?
Hi Stephen, it sounds like the charging circuitry isn’t working correctly. The batteries are supplied with a small amount of charge in them which explains why the brush worked at first and then ran down. I’d advise checking the fine copper wires from the charging coil and that these are all intact and connected to the PCB. Also look for any stray blobs of solder that might be causing a short near that end of the PCB.
Hi Ionic,
Thanks for you reply. I inspected all solder joints with x10 eye glass and all seemed ok. I suspected the newly installed battery was defective so soldered an additional battery in parallel with it and set the toothbrush on the charger (without plastic casing of course. I have a photograph of this if you would like it).
All indications were good and 24 hours later, the toothbrush ran correctly. Having removed the additional battery and replaced the device in plastic case, it ran down very quickly when switched on. At the moment, it is charging but if it fails to hold a charge, I shall change the internal battery for the one I had connected externally. Watch this space!
Hi Stephen,
Thanks for the update. If the battery is defective then we will send a replacement. Let us know how you get on!
Looked like first battery could not hold a charge so I fitted the second one. All is now well. The toothbrush runs as normal although it does take longer to charge. I presume the higher capacity battery will run for longer between charges but will also take longer to charge ?
Many thanks for your patience and help.
I’m glad you got it working.
The higher capacity battery will take longer to fully charge but, as you said, it will run for longer before it needs recharging again.
Happy brushing!
Re Braun 3756…
Couple of points… I fitted the larger capacity battery. Cutting out is fiddly, *but worth it*… It took me about 5 mins in all to carefully pare away – check, pare away – check etc.
I put it all back together, no red light but it charged. 12 hours later, nothing. Price checked a new toothbrush at Amazon & Boots and thought “No!”.
Took the innards out, duff solder joint on the negative terminal! My silly fault! Now working REALLY WELL!
Three tips…
1) I did the work in the kitchen and didn’t want to clamp a vice to the kitchen table… so, I secured the innards with duct (duck?) / gaffer / jungle tape to and offcut of wood (a piece of worktop offcut actually…) – worked a treat.
2) The pressure light wires and the charging coil wires are soldered AND go around little plastic posts. I snipped the extra wire off AFTER the solder joint – it made desoldering and removal much easier – even though I used a solder pump.
3) I didn’t use an electric soldering iron – the job is too fiddly. I have a gas “Silverline” one and a (wait for it)… Aldi “Workzone” gas one. the Aldi was by far the easiest and best to use.
The hot water tip is a great one.
I hope these tips help and inspire.
Thanks Iain! Great to hear your success story and feedback, especially using tape to hold down the brush while working on it.
Happy brushing!
With Rob’s help and the excellent guides, I flew through the initial disassembly. BUT. Despite having soldered many times in my youf, I managed to make a total pig’s ear of both battery terminal solder joints. Too small a space for my thumb fingers. On reassembly, the light flashed fitfully on charger; but there was no joy at the end of 24 hours. Stress on the joints proved a weakness at both ends.
Despite my belief that I had probably burned out the circuit board, leaving me with an interesting, toothbrush shaped art project, two repeat disassembly-reassembly attempts and I am now looking at a brush which astonished me by starting up when I pressed the button. It is on charge now, awaiting the final verdict, but any failure is down to my cack-handedness. Why does the manufacturer make it such a pain to change the battery – as if I didn’t know…
Thanks for the complete guide. I got the new battery in and after putting it on the base the green recharging button starts flashing immediately.
But even after 4 hours of recharging I cannot get it to work. The motor won’t start. I already soldered the battery again, but to no avail.
Also checked the circuit board and the copper coils. All is well with these.
Any idea what it might be?
What type number is marked on your toothbrush Frank?
HI Ionic, Thanks for your superb guides and specific information. I am poised to undertake the battery replacement for my Oral b 9000 (V1) which has been hanging on and threatening for many years. I have arrived at the basket requiring shipping costs and I am unable to locate the destination “South Africa”. Is that an oversight or a consequence of conscious risk avoidance?
Kind Regards, Rob
Hi Rob, We are not currently shipping to South Africa due to the majority of packages sent there getting lost. If you have a friend/relative/colleague in a different country who you will be seeing soon we can ship it to them instead.
Thanks for the explanation. I’ll work on your suggestion and revert. There are a couple of possibilities.
I have replaced the battery on my 3756 with an Exell 2200 mAh, 1.2 v battery. It’s 49 mm long. I got it in and everything, and the battery appears to be charging because originally its charge was 1.2v but now it is 1.4v I have left it charging overnight and for some additional hours, maybe 10 hours total. It flashes green when charging, but when I take it off the charger and try to start it, it immediately flashes red, the motor jerks very slightly and briefly, and it won’t start. I wish I hadn’t taken off the coil because that was the only part I mangled. It looks like the wires are connected though. Would it be charging at all if the coil were a problem? Can you help?
By the way, the motor works and can be run by connecting an external battery with a charge of 1.2v, to the terminals on the PCB. So the new internal battery has plenty of current to run the motor. Yet it won’t run.
If the battery is measuring 1.4V it should be charged enough to run the motor. Try re-soldering the coil wires to the PCB, and the battery tags to the PCB then give it an overnight charge.
I have recently replaced the battery in my Oral B Professional Care Type 3756. I fitted the larger battery and found the instructions excellent and quite straight forward. After charging overnight, the tooth brush worked perfectly without further charge for 17 days. On recharging overnight, the low battery light came on after the first use and completely ran down after a second use. I have now recharged overnight several times and every time the low battery light comes on after the first use. Is this a faulty battery?
It’s possible. What happens if you leave the brush to run continuously? It sounds like it could be a broken charging-coil wire inside the handle so check these and the solder connections to the battery.
I had a battery melt due to a short after less than a year after it fell on the floor. It turns out the spring came into contact with the outer part of the battery. Ionic very kindly replaced the battery for free and I have to report that all is now up and running again for which I am really grateful. Best customer service on the planet.
I recently bought a replacement battery for my Oral-B triumph 5000. I put it in. The battery seems to be bad. I charged it full, and it can not last for two minutes!
Sorry to hear that you’re having an issue. How did you get on with the checks and charge/discharge cycles on our support page?
Oral B toothbrushes have been made with NiMH batteries and some models are still available to buy. However, the newer models are now fitted with li-ion batteries. In your opinion, which is the better one to buy and why? Thank you.
Hi Jeff, replacement Li-ion batteries are harder to get hold of and more expensive than Ni-MH so when they wear out the barrier to repair will be that much higher. Still do-able though! If you buy a new brush, make sure you register for the full guarantee.
It happens that after one year I have replaced the battery of my Oral b, now it doesn’t work anymore.
When placed on the charger nothing happens so it looks as if it’s fully charged, while if I take it and try to have it running it doesn’t work.
Repositioning then the toothbrush over the charger the three leds get lit and if I now try to operate the toothbrush it does work with the red led on, like if it’s now not charged but discharged, infact after 30 seconds it stops running and to have it woring again I have to repeat the cycle.
Place it over the charger and press the on button …
Any hint about what I can do to fix this problem ?
Many thanks for your amazing support.
If you have checked all the solder joints and that the copper wires from the charging coil inside the toothbrush are not broken, then it could be that the battery has died, or there is water damage inside the toothbrush.
Thank you for your answer. Unfortunately, I believe some water could have damaged the circuits …
Thanks for the useful guide. I have one suggestion which is to try a charge cycle and run the brush before putting back in the housing. Then you can troubleshoot any problems easily.
– Adam
Thanks for the tip Adam – good idea!
Hi,
Have just changed a battery in a Braun 3728, no problems encountered till the connections were made then I found that I cannot turn off the toothbrush, have looked at all the connections all look ok can you suggest anything/
Regards
James
It sounds like a stray blob of solder is causing a short circuit somewhere. Or that the battery polarity is reversed.
Thanks, I found a small ‘slither’ of solder laying across components on the board… now all is ok and working fine.
Thanks
Can I pay someone a reasonable rate to do all this for me?
Do you offer a service for battery replacement. This is just not my thing and cant buy all the tools and bits to do a replacement, yet I dont want to throw away a good brush.
Hi Dan, we maintain a list of toothbrush battery replacement services here.
Hi
I bought your Top Quality 49mm x 17mm Braun Battery with Offset Tag on february 12 2017.
I replaced the battery in my Oral-b Triumph and work fine until last week.
Now only one bar is blinking when the toothbrush in on the charge. . As soon I remove the toothbrush, no charge appear.
Before re-opening the toothbrush, Any cue of what may cause the problem
Hi Regis, it sounds like there could be a loose or broken connection. Check the solder joints for the battery and coil wires, and check that the coil wires have not snapped.
Hi.
Just to follow-up on my issue,
I did check the copper coil and it is ok. However, the rigth big solder point, ( the two big solder point in front of the battery positive solder tag) is very hot.
Is it normal or it indicate that something else is causing an issue and something else can be verified?
Thank you for your support
No the heat is not normal. It sounds like there is a short circuit so check all your solder joints and look for stray blobs or whiskers of solder causing shorts. What is the Type number of your toothbrush?
Hi
I have a Phillips Sonicare HX 9340 toothbrush. The rubber seal where the head fits onto the body has perished and split, as a cosequnce when the brush head was removed the shaft or spindle came out with the brush head.
Do you know if this seal is repairable and if so where I can buy the seal. I’m assuming the body will have to be dismantled as in your battery video. TIA
Hi Ken, Yes spare parts for your Sonicare DiamondClean are available, including seals and shafts. Take a look at our Sonicare spare parts page for details. As you suggest, use our repair guide to help you open up your toothbrush.
Hi,
Is there any information up to what voltage a li-ion battery being charged in Oral-B Pro 2 and Smart 4000 series, please?
Just to understand could I hold those brushes on charger permanently with no serious battery health decrease.
It’s safe to leave the Li-ion powered brushes on permanent charge but it will decrease their overall lifespan. Li-ion batteries like to be stored between 30% and 80% charge but it will be difficult to achieve this! Best practice will be to recharge it until it is full then use it until it is nearly empty before recharging.
Have just bought my first electric toothbrush. I can’t even get through the packaging ..
how should I do this?!
problem solved with a sharp knife!
Just to say thanks for both the extremely helpful guides to battery replacement and the prompt battery buying service. Clear descriptions and good close-up photographs meant I was able to follow step by step with the replacement. Had to cut the old solder off because I couldn’t get the existing solder to melt and was afraid of burning the PC board, but all worked out in the end.
The toothbrush is looking good and charging right now 3hrs into its 24hr First Charge, touch wood, everything fine tomorrow.
Without your help it would have been a new toothbrush so extra thanks again. Great to be able to repair a modern appliance, thought those days were over.
regards
John
Hi,
France is not available in the shipping list.
Thanks.
We can send orders to France but please be aware that you might have to pay VAT to French Customs when the order arrives. This is because sadly the UK has left the EU.
Please see our web page for an explanation of the VAT for different EU countries here.
If you still wish to place an order you can select your country as ‘French Southern Territories’ but also add the word ‘France’ after your city name. We will then change the details in our system.
If you have a friend, relative or colleague who lives in another country nearby such as Belgium (€22 threshold) you could have your order delivered to them to avoid paying VAT and any VAT collection charge.
Can you please confirm which battery and tutorial is used for model HX9120?? Thanks.
You can probably use our Sonicare DiamondClean battery replacement guide for your FlexCare Platinum HX9100 series.
Cool, thanks for the quick reply!!
Then I should order the same battery in the tutorial??
Thanks again!!
Assuming that there is no water damage on the circuit board then yes, it’s the same battery.
I’ve replaced the battery in my Oral B 3756 using your excellent repair guide and a new 2200mAh battery. I put the brush with the new higher capacity battery on charge overnight . The green charging light flashed although it didn’t seem quite as bright/solid as previously. After leaving on charge for almost 24 hours there was no activity when the on button was depressed.
I checked my soldering connections which seemed solid and for overflow but couldn’t see any obvious short circuit points.
I desoldered, dismantled and removed the battery and decided to charge it using my battery charger. I left on charge for around 20 hours and measured 1.411 volts .
I’ve now reassembled but still no activity or lights when switched on.
I’ve checked for continuity on the motor terminals and the charging coil terminals, each of which shows zero ohms and therefore an uninterrupted circuit.
Do you have any advice for me please?
Hi John, now that it’s reassembled, put the brush on charge for 5 seconds to check that the charging light flashes. Then take it off the charger and try switching it on. It should either run or flash the red battery symbol.
Thanks very much, it runs!! 🤗
I am having real trouble getting the top cap back on (plastic piece when toothbrush head is) any tips? I have tries with pliers and a spanner?
Do you mean the plastic ring at the top of the brush? Make sure the innards of the brush are pushed fully home so the shaft extends fully out of the casing and you can see the groove around the plastic shaft that the ring clips around. If you heat up the ring in near-boiling water and then carefully remove it without scalding yourself this will give it some flexibility. Then press it into place with a ring spanner.
BUONGIORNO
ho utilizzato la vostra guida per sostituire una batteria ad uno spazzolino Braun Oral-B Triumph Professional Care 5000 TIPO 3762.
una volta messo sulla stazione di ricarica lampeggia il solo led verde in basso e la ricarica sembra non essere completa.
non ho più il manuale di istruzxioni quindi non so se sia un allarme oppure una segnalazione.
avete consigli?
grazie
Hello, Have you left the toothbrish chargng for 24 hours? If only the first green LED is still flashing after 24 hours then check items 3 and 4 on our Customer Support page.
I have a Braun/Oral-B model 4726 toothbrush with a dead battery. The battery is about 2mm smaller in diameter than a C-cell and about 2mm taller. [ 7/8″ / 22mm diameter; 2″ / 50mm long ] It consists of two cells. Each cell has tabs; the tab on the + end of the lower cell is soldered to the bottom of the upper cell. The tab on the + end (top) of the upper cell was cut off. The cells look to be stainless steel. They were wrapped in yellow shrink-wrap plastic with only “Japan WL”. No markings on the cells themselves. Any ideas what the battery is?
It sounds like the battery pack in your Type 4726 is similar to that used by some Waterpik Flossers. We have details of this 50mm long pack on our Waterpik Spare parts page.
I’ve just changed the battery in my wifes Philips sonicare toothbrush, on reassembly the brush cycles through the different modes by pressing the power switch but doesn’t run. When charging I get an orange light followed by a double flash green, any idea where I might have gone wrong?
Hi Team,
What a fantastic resource! I volunteer at a repair café and am trying to fix an Oral B 3756. When placed on the charger the green light flashes, but doesn’t extinguish even after 24 hours. When turned on, it works for about 2 seconds, then the red light flashes and the motor stops. There appears to have been water ingress through the (perished) silicone over the switch, since there is a hint of rust on the motor casing, and there was some condensation when I removed the internals from the case. The battery measures 1.4V. The coil terminals are fine. The rest of the PCB appears optically OK.
I can probably obtain a replacement housing from a defunct brush on eBay, but don’t want to replace the battery only to find out that the PCB is faulty.
Any suggestions? I hate throwing things away!
Mark
Hi Mark,
The water ingress sounds like the cuplrit here. Battery voltage is healthy so it is likely that moisture has damaged a PCB track or component. Try cleaning both sides of the PCB with isopropyl alcohol to remove any mineral deposits or crystals that might be causing a short.
Thanks so much for the prompt suggestion. Sadly, even though the alcohol treatment made the PCB look sparkly it looks to have a fault. Unless you have any other suggestions, I’ll strip it down into parts for recycling.
Best wishes
Mark