Philips BT9290 Shaver (as Well As Others) Revival/refurbishment
Introduction: Philips BT9290 Shaver (as Well As Others) Revival/refurbishment
We live in the days where more and more devices are made with non-user-serviceable prebuilt batteries. This approach can be somewhat justified with cell phones, where it is much easier to make watertight/dustproof if the case is glued/sealed together. When the battery dies on such a phone it is probably going to be already 2-3 years old and considering the technological advancements during that time, the majority of users will want a new phone anyways. Unfortunately, we see this approach also being applied to other devices, like this Philips BT9290 Shaver, although it's in no way unique, as the majority of all other manufacturers do exactly the same. Justified or not, I personally prefer to choose devices which have an easily accessible battery compartment, although it seems that in some categories of products this is a thing of the past. A little surprising considering the "right to repair" laws being put in place, where the batteries are something most likely to fail first, and thus should be easily replaceable.
So, how did I end up with this shaver? I won it in a contest for the most creative shave - just check out that "lizard" on the top of my head.
On the side note, the title states specifically Philips BT9290, but you will also find general tips, on the approach you should apply, taking apart any other similar shaver. Also, beside the text, you can view a video detailing the whole process, where it might be easier to see, how the certain components should be disassembled and then reassembled.
Supplies
* Shaver with dead batteries
* In the case of this Philips BT9290 - two AAA 750-800 mAh NiMH cells
Step 1: Disassembly - Basics
Let us start the disassembly by popping off the shaver head and looking if this exposes any screws underneath.
Seeing the two Philips head screws on top, we can proceede and remove them.
As this didn't do much, we need to establish what next should we try removing, and this is a bit of trial and error, as pulling too hard on some of the elements and we will break them.
It is therefore important to first try to slide the plastic elements (in case they have L-shapped hooks) before trying to pry (also gently) them up.
Step 2: Top Panel Removal
As sliding the panel didn't do much,we wedge our fingernails under the top edge of the panel and try puling it up. 267
With a little force it snaps off, exposing another set of screws, which you should remove.
Now you can try sliding the metal cover in the direction of the power inlet socket, which will also allow for its easy removal.
Step 3: Removal of the Internals From the Outer Shell
As we see another screw exposed, it should also be removed.
Now the more difficult bit, you need to push down on the guidenance laser and pry up the top of the internal subassembly and once it is half-way up, move to the bottom and push in the power supply socket, to release the entire subassembly.
Step 4: Removal of the Guidenance Laser, Top Cover of the Internal Subassembly and Cutting Height Regulator
Unscrew any screws left on top of the internal subassembly, which are now exposed.
Remove the guidenance laser, which is a separate sub-assembly.
Slide off the top plastic cover, followed by the cutting height adjustment ring subassembly (try to remove it as a whole, so that later you won't have to worry how to put it back together)
Step 5: PCB Disassembly
Here's another bit, which is a bit more difficult.
In order to get to the PCB board, you need to pry up the snaps on the sides of the white plastic cover, which should be done all at the same time, to get it removed. If you have any difficulty, you can use toothpicks etc. to keep these pried up, but be careful not to bend them too much, so that they won't break.
Once you have the cover off, the PCB surprisingly comes right out with a little prying, as it is just pressed in place.
Step 6: Battery Removal and Selection of Replacements
A quick glance on the original batteries. This unit uses 750 mAh AAA NiMH cells. When performing the replacement, it is important to use good quality cells of similar capacity and type. It might be tempting to install something of much higher capacity, but we don't know how the electronics exactly operate in the particular shaver and you don't want the batteries undercharged etc. as improper charging characteristic can quickly degrade their performance. 713