The on/off button is not working (3 years old)

Sandra, November 2007

I yanked off the metal button on/off button with a pair of pliers and put it back on the charger and it stopped turning itself on.
Maybe I'll get another month or so out of it.

Linda, November 2013

My battery voltage is okay. A current of 1 A could be drawn from the battery (measured for a second).
As I couldn't see any disconnection at my switch, I left the soldering points of the switch as they are.
Trying to reset the microcontroller I disconnected the minus pole of the battery. Reconnect after one hour did not start the motor.
What do you do in case the battery voltage and the switch are okay?

Saint, February 2012

I had exactly the same problem as DW, where the switch on my sonic complete became disconnected from the board. But as the contacts on the switch were too tiny for me to resolder myself, I just soldered a very thin cable from a broken headphone to the contacts on the top right and lower left of the switch - those are the 2 important ones. Then I led the cable out through the tiny battery release hole at the bottom back of the toothbrush. Add a small switch of your liking - preferrably waterproof - and seal the hole with a drop of glue. viola :)

wolle, November 2010

My Sonic Complete would get more and more difficult to turn on. At first it only happened once in a while, then all the time, then finally I'd have to press the button dozens of times and/or hold it in to get it to turn on. This happened over a span of several years. The problem first appeared after I had the brush about 16 months.

After finding the notes here and the video showing how to take apart an older Braun model I did the same on mine. I was surprised at how easy it was to take the tooth brush apart.

The actual power switch is a small microswitch mounted directly on the main circuit board. The external button presses on this microswitch when the user pushes the On button.

So, this wasn't a problem of the switch sliding down and needing to be pushed back up as noted in another post below; nothing had moved or shifted.

This mircoswitch sits on the circuit board and is electrically connected via 4 tiny solder joints. I suspected that there might be a break in one of the joints, causing intermittent contact. Pushing the on/off button places stress directly on the switch, which sits directly on the circuit board. If the cct board is not rigidly connected to a large, stiff surface the board can flex slightly, eventually causing one or more of the solder joints to crack and fail.

I have a small tipped soldering pencil from my days as a electronics technologist so I just resoldered all 4 joints.

Bingo, problem solved. My Sonic Complete now turns on and off each and every time I press the power button. I should have done this much earlier, instead of frustrating myself by having to press the on/off button over and over.

If you don't know how to solder and/or don't have the right tools, ask around and see if any friends could do it for you.

DW, November 2009

I changed the battery in mine and posted the results on instructables.com. The NiCD Sanyo 600AE with solder tabs worked perfectly as a replacement for the original battery.

chogan, July 2009

Good advice--about slipping down.

Fixed in 2 minutes.

Thanks

averla, June 2009

Not so much an answer but a request with some information...
anybody know where one can get a battery replacement. it seems to be a sanyo ni-cd (nicad). I cannot get a reliable voltage from the cell pack( its made up of two smaller tagged cells) as the batery is dead.. but it reads 2.58 volts under no-load... so I suspect its a 3 volt part ( 2 cells at 1.5 volts)...

piers, May 2009

Just in case somebody else finds this page - I think the answer to the problem regarding the on/off button is that the whole innards have slipped down the casing and just require the base to be removed carefully as instructed above - making sure that you don't break the 4 thin and unmarked wires from the induction coil in the base - and then just push the internal unit up. There is only the spring to prevent the inards slipping down and I found - after breaking the wires - that the unit was working fine without the case.

gadgetmadman, March 2009

Not exactly an answer - I have the same problem (3 years old, apparently faulty switch)!
However, the switch is ok and so is the battery voltage. It seems to be run by a microcontroller and I'm wondering whether I can force a reset. I'll disconnect the battery (which should do it) and see what happens when I reconnect. If anyone else out there has got this far, I'd like to hear about it.

Graham, October 2008

I drilled out the little plug at the bottom around the back then twited the end capoff.However doing this usually breaks the copper wires as mine did.the contact points also need to be broken fre from the battery.You wont see hat voltage the battery is either.We can get pretty close by seeing what voltage is kicked out of the charging unit (see your manual).
Mine is all strpped out but I think its one for the bin in all honesty.
In truth I wouldnt buy one as expensive as this again as its the batteries that fail first.

Roy, April 2008

This may well be the battery that has given up the ghost. Braun say this should not be replaced but in theory if you can find a suitable one it can be. (I am looking for one myself) If you place the bottom of the toothbrush on the projection on the rear of the charger and twist you should be able to remove the complete assembly.(after removing the head)
Test the battery or temporarily attach another whilst you switch on.
The coil unit attaches to the base by a bayonet type fitting and is quite tricky to reassemble.
If all else fails buy a new one as they are half price (£50) at places like Tesco at the moment

Cal, December 2007