I think my FW3X is DOA. Here is a 2-minute video:
Note I say the wrong battery URL. These came from 18650BatteryStore.com

I’ve also tried 13 seconds and hold. Hold the button for 3 secs when screwing the cap back on.

Bought from Lumintop direct. Everything I’ve read says returning to Lumintop is pointless. They’ll likely call it used or say whatever is wrong is not under warranty. I wish I’d done that research before buying.

Any advice?

Metal/contacts should be clean but it wouldn’t hurt to double check that. Is the switch retaining ring tight? Could remove and replace that, check for anything obvious on the switch board. If no luck, I’d email Lumintop, wait a couple days for no reply, then try messaging them on Amazon. Their rep their may take care of you, especially if you send the link to the video. (I’ve been dinking with him for almost a year now trying to get warranty assistance with a discontinued light…friendly and did attempt to have a driver sent to me, but it was totally the wrong driver…since then it’s been “let me check and I’ll get back with you” followed by me periodically sending him a message of inquiry. lol. But…you may have a better chance here since the light is brand new and still available.)

Failing all of that, try a dispute with your payment processor once you get no reply from Lumintop. They may reply and take action then, and if they don’t then you should see a full refund.

Edit: you might also try contacting Neal to see if he can assist.

Could you have accidentally put a battery in the wrong direction?

My recollection is the FW3X uses the Lume1 driver, which does not have reverse polarity protection.

Putting the battery in the wrong direction for even half a second will toast the driver. That’s what happened to a Lume1 driver I stuck in an FW3A.

Good video, good luck figuring it out.

Oh man. Yeah. I did… the very first thing out of the box. Bummer. Guess this is on me.

Any lower-cost way to repair the damage? Paperweight?

Whoops. :slight_smile: Well, if you’re handy at soldering and don’t mind the extra fiddle factor in this light, you might be able to get a replacement driver. Neal’s Gadgets is probably your best bet there but if you can get Lumintop to reply to you then they should be able to sell you one also. Reply rate to email/contact forms is pretty low, it seems.

Thanks. I shot Neal an email.

i thought the original FW3A at least, could handle reverse polarity

at least i thought it was mechanically protected somehow

i also think i have done that with mine, it still works


FET+7135 drivers like in the FW3A just require a diode before the MCU for RPP, which the FW3A driver has. Switching drivers like the lume1 in the FW3X require a power PFET which this driver doesn’t have -> insta kill upon reverse cell insertion.

Instead of DOA, it should be KOA :smiling_imp: :smiley:

For the driver, if you can get it from Neal, try contacting Lumintop directly asking them to sell you one.

Lumintop included the FW3A manual with my FW3X. The FW3A manual doesn’t warn about RPP.

Would you all agree this puts the responsibility back on Lumintop?


All lights should have reverse polarity protection at this point.

Absolutely for the omission in the manual, plus the lack of RPP itself.

Wasn’t there a paper like this in the box?

As much as I agree that lights should all have RPP for protection of the user and of the device, I am not sure if the brand can be blammed/culprit by someone’s fault while introducing the battery reversed. Specially when there is info available on how to do it.

I once had a flashlight almost exploding because I introduced the battery reversed. I got indignant but couldn’t blame them for my fault, honestly.

Have you read it before inserting the battery?

I’m happy to take responsibility if the consensus here is that I should.

One can certainly argue that instructions on how to do it are distinct from warnings not to do it wrong. That aside, explaining that this device does not have a feature that most equipment would consider standard probably also bears mentioning somewhere in the marketing material (web site product page).

I feel you, I do!
Here’s my thread when I had that issue I mentioned above with the Manker E11 and a 14500 cell: Manker 14500 battery overheats and leak (in Manker E11)
But clearly, that was my fault as now I guess it was yours!
In my case, the battery didn’t explode but was close, and the driver didn’t get damaged, unlike yours.

This aside, yes, all lights should have RPP and that should also be stated in the User Manual!

Nah. Mentioning missing RPP in the manual is not sufficient. A light should be inherently safe. Once I had an R50 Pro from someone on my desk. It smelled like it could cause all sorts of lethal deseases. The original battery has a friendly fat arrow printed on its wrap, indicating how to insert it. Still, that was obviously not sufficient.

Whether lights should have RPP, and I think they should, is different from whether they must have it. I don’t think that a manufacturer is under any obligation to provide a feature that many think is beneficial/necessary unless there’s some mandate that they do so.

If it was me I’d chalk this up to a learning experience.

Edited to add that I think it’s a slippery slope that we need to be protected from any actions we take that might cause harm or something to fail. When I’m working on my car or reloading I sure as heck make sure that I’m careful in what I’m doing. Inserting a battery the correct way is no different from connecting car battery wires correctly.

I’d argue cars should have reverse polarity protection as well though.

Reverse polarity protection should be a standard on all things sold in my opinion.