FW3A Troubleshooting / FAQ

A potential small short sometimes happens under the led when too much solder is used. If the negative pad of the led develops a tiny bit of continuity to the thermal pad next to it, you can get what your describing.

Have you tried swapping that mcpcb for one in another light? That would tell you if the problem is with the led or the rest of the light.

On the light that “started doing it on its own”, yes I’ve changed the mcpcb and leds entirely, as well as new emitter leads from the driver.

The “factory broken” one I haven’t removed the mcpcb. This light had evidence it had been used in some manner prior to arriving, I got a refund but its a Fw1a and I want to fix it and swap the emitter!
I might remove the board and hook up the emitter wires to a multimeter if I suspect it’s not the same issue on both lights.

Okay, so you’ve narrowed it down to the driver. It can be tricky finding a short in a driver. First thing I’d try is clean both sides with a toothbrush and alcohol. You can look over it with a magnifying glass for any solder that looks out of place. Most likely it’s one of the 8 current regulator chips. A tiny percentage of them can short a little. You may have to unsolder them and replace with new ones. It could be the FET leaking, but it’s a harder job to remove it. You typically need hot air.

I bought an FW3A on Amazon a little over two months ago. This is a new type of light for me and I love it. Everything works except I noticed that now it always turns on at Max Ramp. I thought it was supposed to (and used to) turn on a whatever level it was at when I turned it off. I’ve gone over the Anduril UI (thank you ToyKeeper) and can’t find any reference to setting or locking in the level that it turns on at, although I thought I saw a YouTube video recently that made reference to it. Anyways, I couldn’t find anything in this thread about this problem. Should I just try a Reset? If so, which one, press and hold the switch while screwing the head on or 13 clicks and hold on the last one? Will either, neither or both work?

If it has the reset feature, it would be 13H. You have manual memory enabled. Turn the light on and do 5H to disable it.

I opened the first one I had, from the original GB run, just out of curiosity. Never carried it because I hated the switch so much, and traded it for a knife.

For my purple, it was a shelf queen until I opened the tail to do the o-ring mod. Now it sees use and carry time.

Also, it feels like half the FW3As out there need to be opened and fiddled with just to get them working right to begin with.

Thanks SammysHP. I turned it on. Then 5H, and it now turns on at the level it was at when turned off. I’m pretty sure that is not in the manual that came with my light. Maybe my light shipped with a new version of Anduril but not a new Manual.

This UI diagram has the manual/automatic memory, and for some reason I also have an easier time reading this one than the normal UI diagram. :

I found this on reddit and don’t know the source, sorry!

I’ve got one fw3a that now displays this same issue. Happened after I shorted the +wire to the shelf like an idiot. I think my best guess was the mcu was the culprit. Never dug into it though as I’m also looking forward to the Lume1 driver

Correct, Lumintop have updated the Anduril version at least once (compared to launch model).

Launch models did not have manual memory, new models do. I think maybe factory reset was not present on launch models also.

They did not update the included manual. No big deal since only minor changes to UI.

Right, except when I inadvertently change a setting that is not in the manual and have to turn to the internet to figure it out. Thank you BLF for your help.

I understand them not printing a new manual, especially if they have a large quantity already printed. Maybe they could include a small slip of paper saying something to the effect of “Anduril UI has been updated, go to this website for the latest features.”

My FW3A won’t turn on after I let someone use it and trying to unscrew the tailcap.

Battery is fully charged retaining ring seem tight enough.
Clicking or holding down the tail e-switch does not turn it on.

Have you tried removing the head and loosening then retightening the tailcap, reinsert the cell (it is charged?) And then replace and tighten the head?

Did they just loosen the tailcap a little or actually remove it? If it is a version without the newer tailcap that has the retaining ring they may have lost the little “nub”

Thanks MtnDon

My version is from Mid 2019.
I am not sure what exactly happened to the tailcap but I assume it could have been removed.

Yes I removed the head, tightened tailcap and Yes Battery is charged

You could try loosening the retaining ring in the tailcap slightly. That helped with a poor contact on an FW3 for a period.

I loosened it a bit, sofar no joy, it is not turning on, and also no “blink” - battery check on contact. but I appreciate your suggestion,

You don’t get the power connected blink? That is a basic function not connected to the switch or inner tube. It’s just battery power going through the tail cap and battery tube to the head. This explains the switch not working. The driver is not getting power.

You will need to start with the basics. Take just the head and attach a battery to it. Then use a wire to go from the battery negative to the exposed threads on the head. Stick the wire end next to the battery to reach the threads.

If too hard, install the battery tube minus the inner tube (we will assume good contact from the head to battery tube) then run your wire from battery negative to the exposed threads on the battery tube.

You should see the power connected blink. If not, there is a problem in the head. Try loosening and then tightening the driver retaining ring. Make sure it’s sitting flat and is centered. Test again to see if it gets power.

If not, remove the TIR lens and make sure the wires to the leds are still attached. If so, the problem might be in the driver which is a bit more complicated to diagnose and requires soldering equipment.

Also, try wiping the threads clean, using a little bit of conductive lubricant (“bulb grease”)
A bit of grit can cause a lot of misbehavior.

Just a quick warning: “Bulb grease” is not conductive. It is an insulator used to protect electrical contacts from water/corrosion and arcing. The electric connection is made by the contact points between the two objects.

Sadly this misinformation (that bulb grease is conductive and that conductive substances should be used in flashlights) is shared by hank repeatedly in this forum.

Using any kind of conductive substance in your flashlight will cause shorts and other issues at some point.

good to know, thank you for the heads up. I always use bulb grease when changing my car’s headlights. Always assumed it was to keep rain water out, not help with conductivity.