Driver issues with Lumintop FW21 Pro

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Yourrid
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Driver issues with Lumintop FW21 Pro

Hey gang, I’m having trouble with my Lumintop FW21 Pro. As soon as I start screwing in the tube, the emitters flicker, ramp up, ramp down, and then go to the lowest mode. It’s impossible to turn it off. I tried ruling out tube and tailcap issues by wiring a 18650 directly to the + spring, and the – to the side of the driver/head. Still have the same issue. I think the driver may be toast.

1st video: tailcap is on tight. Samsung 21700. Light automatically turns on without me touching the tailcap.

2nd video: I have it hooked directly up to an 18650 to rule out tailcap issues.

I took the reflector out as well to rule out grounding issues. Can anyone please help!

BOO5TED
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I had a similar issue with a FW3A that I have. I was mixing heads, bodies, and tailcaps with a few different ones that I had. I noticed the one with the issue was one I left out the pocket clip. Once I put the clip back on the light it worked as it should. I wonder if the little bit of space the clip takes up had something to do with it.

"America has three cities, New York, San Francisco and New Orleans. Everywhere else is Cleveland."- Tennessee Williams

 

Unheard
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The driver seems to work. What you see is a reset and a subsequent safety parking at moon.

The switch contact is permanently bridged. Mechanical problem.

Smile, you cannot kill them all.

Yourrid
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I FIGURED IT OUT!!! Cool

I tested the tailcap against my FW3A, and it worked perfectly. Tested the tube, just like the FW3A, worked just fine. So I knew it had to be something with the driver. In frustration, I tightened the head onto the tube as HARD as I could, and it started working normally Flat Stare

So I look at the bottom of the driver, and am trying to understand how metal sleeve in the tube works, how the electricity flows to the driver, how the tailcap works, (contemplated the universe) and realized the brass retaining ring for the driver is TOUCHING the negative/ground/cathode pad on the driver, that the sleeve is supposed to be touching. (Yellow line)


So it was, in essence, short circuiting. The driver was bypassing the momentary tailcap switch and staying powered on continuously, and could not be turned off. ToyKeeper must have installed a safety mechanism so if the firmware gets continuous power on startup, it goes into this low/dead mode. When I really screwed the tube down hard into the head, it must have flattened out the driver and gotten it away from the metal retaining ring.

Due to the EXTREMLY strict tolerances between the driver pad and this metal retaining ring, I opted to take the ring out. My FW3A doesn’t even have one, so I’m not sure why the FW21 Pro has one. Seems like too tight of tolerances to be trusted.

Why this ring is metal instead of plastic like the retaining ring in the tailcap???