My favorite favorite favorite AA/14500 flashlight died - I think she ran it through the washing machine :person_facepalming: many months ago. It is an XTAR WK41. I kept it hoping it would magically start working again but after trying it for the like 10th time I resign myself to the fact it is dead, at least beyond my skills. I will ship it for free to any of you guys with more skills than me who can make use of it.
I can try to fix it for you and ship it back. Iām not the best modder on here, but Iāve fixed lights in worse shape. Itās your favorite lightā¦you canāt just give up on it 
Is it glued shut anywhere?
Ironically, Iād suggest taking it apart as far as you could go, and rinse out each piece thoroughly with water then alcohol (IPA).
Iāve taken apart whole terminals that were caked with dirt, dust, hair (yecch!) and other nasties, and soaked āem in a basement sink with water and SpicānāSpan or similar. Floated the CRT in it. Brushed everything clean with detergent, inside and out, even coils, trimmers, keyswitches, you name it. Put āem back together and it all worked perfectly. The key is to make sure you wash out all residue. For trimmers and switches, any mechanicals, soak āem with contact-cleaner and -lube.
So, SpicānāSpan and water, detergent and water, water and water. More water. Even more water. Maybe a little more water. Cleaner/Lube on the mechanicals like trimmers and switches. Pray. Reassemble. Try.
That was for disgustingly grunged terminals. For a light that maybe got run through the washing machine, a good soak then rinse with water might be best. Then let it dry thoroughly. Treat the switches with contact-cleaner, see with a meter whether/not they switch reliably. If not, replace the switch(es).
The side-clicky is probably the weakest link, so Iād start there. Residue might be keeping the clicky from, well, clicking. Without contact, it wonāt turn on, let alone change modes.
If you donāt get yours fixed and do end up giving it a way, send me a pm if you want a wk42.
WillyD - PM me your address and Iāll send it to you, no strings attached. You might fall in love with it and decide to keep it if you can breathe life back into it. And if it does come back I guess Iāll have to do a giveaway of something nice
Lightbringer - I tried cleaning it but was not successful. Quite possible it was my amateurish methods, but I did give it a once over.
Lightrider - thank you for your generous offer!!! But CR123 isnāt a battery I use in other lights so probably not a good worth getting from you. Iām using mostly AAA/AA/14500/18650.
Thanks, you guys are great!
I had WK41, excellent light only drawback was that the button is quite low profile, not that easy to press even for medium size thumb, it was one of my favorite lights, but I needed the money and I sold it, what a mistake that was. Now I am left with WK42.
Btw, bezel is not glued, itās easy to get to the led and the driver is screwed with 2 screws so also easy to get out but, components are so small, it is very difficult to work on them by handā¦
i had a wk 42 and it failed due to an inductor not being glued on well, came off and broke its wires
wle
Thatās why I always debate when rolling my own, whether/not to pot them. Makes it rather permanent, but keeps the innards from bouncing around even if you toss the light against a brick wall. Other things will break before parts come loose.
wahoowad, received the light today. This thing hardly looks used. Easy to open up and found no signs of water ever entering. The led tested good as well. I was actually hoping the led wouldnāt work as that would be an easy fix.
You nailed it!
If I can find the other end of the wire I may be able to reconnect it, but doubtful. The numbers on top of the inductor coil arenāt legible, so Iām not sure what size it is. Iāll search the forums and see if anyone has posted pics of the WK41 driver.
I tried gluing the inductor back on and then rewinding it. The led was working, but was very dim. I harvested a 2.2ĀµH inductor from another driver and tried on the xtar driver. The led was brighter, so it certainly is the inductor. This 2R2 inductor visually appears smaller with fewer windings than what was on it. Unfortunately, I couldnāt read the value on the broken one. Iām sure Iām close, so itās just a matter of finding the correct one. For me anyway, inductors arenāt a component I typically use or change around, so I donāt have any others. In my next parts order Iāll throw in a bag-o-inductors. Bad news is that I donāt currently have the part, but the good news is that this should be an easy fix.
This is from the 42. Donāt know if they would be the same though. Looks like they are base on the driver id.
LightRider, thanks! Yes, I think thatās the same one. I could read what looked like a āDā, however it didnāt make sense to have a āDā at the beginning of the value. Going by yours, Iām guessing that is 100 or 10ĀµH (neither D01 nor D0I make any sense to me).
āD01ā would be the deviceās āhouse numberā.
Eg, for ICs, there simply might not be enough space to print āLM311CNā or such, so āH14ā or āB06ā might be its house-number.
Not to be confused with a date code, lot number, etc. Sometimes a Big Buyer will get an assload of devices from the mfr, and instead of being spelled out (for people like us to try to look up and reverse-engineer in a way), they list shorthand house-numbers instead.
Ok, appreciate the explanation. In that case, I guess itās just going to have to be trial and error.
Iām pretty sure it said 100. But I am not 100 percent sure. 
Since the microcontroller is on the e-switch board, does anyone know if itās possible to utilize one of the cheap 1-mode boost drivers from say KD or FT and connect it to the switch board? I havenāt given up on fixing this. If anything, I can harness the inductor.
Wow this is why I love blf so much! All good people coming together to save a good personās good light!
And thatās a good night from me for today.
India Pale Ale, right?
Oh, you betcha. 
Hey wahoowad, I see you havenāt checked in for several months, but I havenāt given up on this light. Iām putting in an order to one of our overseas friends in the next few days, so Iāll throw in one of those $1.50 drivers and pull the inductor off and see if I can get this thing working for you.