SmallSun ZY-T620 arrived with a faulty switch. What are my options?

It arrived not working so I tried the tailcap from my TR-3T6 and the light worked. So the switch is bad and I'm not sure what I need to get to make it work.

http://www.dealextreme.com/p/smallsun-zy-t620-xm-l-t6-1200lm-3-mode-white-led-flashlight-2-x-18650-108293

Hey, Joe! Have you tried tightening the retaining ring in the tail cap to make sure the connection in the switch is secure? If that doesn't work, disassemble the tailcap and clean all the parts, then reassemble it and try again. Usually a good cleaning and reassembling takes care of things. If that doesn't work let us know.

Ok, I tried all of that and still now luck. All of the solder joints look solid so I wonder if it isn't the clicky switch itself that is bad.

you need to meter the switch for conductivity outside of the light.... click ON "BEEEEEEP" - click OFF- click ON "BEEEEEP" - click OFF

If it passes that test, then theres a connectivity problem with the end of the battery tube and the tailcap threads or switch retaining ring.

If you dont have a meter, one way to check is to unscrew the ring and switch from the cap and just hold them in a stack, and press them all together to the -B tube and see if you can get it to work. like this...

Does the T620 even have a normal clicky switch? Based on some of the descriptions, it sounds like it would have a soft digital switch...

If you do the above and confirm the switch internal gutts do in fact work... then I am guessing the switch ring needs to make direct with the bare metal on the end of the battery tube.

I found some better pictures of this light on Manafont...

So this tailcap design is NOT supposed to conduct -B current through the tailcap threads... because the corresponding body tube threads are anodized. So that means the bare metal -B end of the tube needs to tighten down against the 2-hole retaining ring in the switch cap. This kind of design can be problematic in that many switch designs do not allow the 2-hole ring to sit "out" far enough in the cap to bottom-down against the battery tube end.

Post back what you find out... and we can proceed from here. GOOD Luck!!

it isn't a normal clicky switch definitely...

oh wow... definitely NOT a clicky. Got a live E-switch there. OP, I am not sure if the diagnostic steps I posted above will work for this design... although for just checking basic connectivity I think they should still be valid.

Good Luck!!

Ya, that is the switch. I was just about to post a picture. Well I cleaned it again and blew compressed air on it. Then I reassembled and now the light finally works but it's acting strange.

It has three mode. High, fast strobe, and a very slow strobe. I also have to cycle through all of the modes in order for the light to shut off.

Another interesting thing is if the switch is clicked and held, even very shortly, it turns on. It starts with only medium brightness though. If I keep holding down the clicker the light continues to get brighter until it gets to the "High" brightness. If I stop holding it down as soon as it comes on each click after that increases the brightness slightly, almost like it's adding ~0.1A each click. A very fast click is needed to shut it off. I'm not sure if this is normal but I haven't noticed it on my other lights.

[quote=-JOE-] ...but it's acting strange.

It has three mode. High, fast strobe, and a very slow strobe. I also have to cycle through all of the modes in order for the light to shut off.

Another interesting thing is if the switch is clicked and held, even very shortly, it turns on. It starts with only medium brightness though. If I keep holding down the clicker the light continues to get brighter until it gets to the "High" brightness. If I stop holding it down as soon as it comes on each click after that increases the brightness slightly, almost like it's adding ~0.1A each click. A very fast click is needed to shut it off. I'm not sure if this is normal but I haven't noticed it on my other lights. [/quote]

It's my understanding that what you are noting is the normal operation for this light.

x2.. it has a ramp up (or down) operation thats not explicitly described on the various www sites.

So it is functioning properly?

Having to cycle through fast and slow strobe before it turns off is also normal?

I believe that is the case too.

One thing to keep an eye out for with any E-switch is parasitic drain. The better designs will not deplete the batteries significantly. The bad ones can discharge cells in as little as 2-3 weeks. If this light does have a lock out tailcap (like I suspect it may) you could simply unscrew the tailcap a bit to turn it off, this would bypass all the modes to power it down. Doing so would also cut off -B and alleviate parasitic drain.

I wonder how hard it would be to re-flash the EPROM on this one with a custom UI?

I was actually wondering about that. I have a lot of lights and I bought this light just to see if it was a good, cheaper alternative to my STL-V2.

Overall I am not impressed with the light. The gaps between the tube pieces are very tacky and make the light look unfinished. The square tube piece also doesn't do anything. I think it is suppose to stop the light from rolling but it doesn't. High-fast strobe-slow strobe modes is simply god awful. I don't like going through any more than 2 modes before the light turns off and this requires 3. I also don't like the e-switch; I prefer a traditional switch. The crown is also to aggressive in my opinion. I have never really understood the need for an "assault" crown.

If someone is looking for a XM-L thrower get the Fandyfire STL-V6. I have ordered 4 of them and the only problem is one of them was slightly off center and didn't produce a very uniform beam. It was gifted to my dad because it didn't both him like it bothered me.

-Joe-

Thanks for posting your observations about this light... I also thought it would be a decent budget alternative to the STL V2 FF V6 but the mode arrangement and E-Switch were odd choices. I thought a driver and switch upgrade might help, but by that time, it would cost as much as the better light. Since you aren't impressed with yours, I think I'll hold out for the real thing, unless I get a TR-3T6 first instead...

The Fandyfire STL-V6 is the most impressive light in my fleet so far. It is also the light that people ask me about the most. It just throws so well.

People always say, "Get me one!", then they ask what kind of batteries it takes and I say 18650s. They look at me like I'm crazy and ask if wal-mart carries them. I just chuckle and show them my sipik.

Just tell them it uses the same batteries as their laptop computer pack has. Laughing WalMart sells laptops...

Hah, ya my airsoft (crane-stock) lipos also use 18650s that are similar to IMRs.

They are pretty common but not enough for the average person to understand. Most people don't seem to want to mess with rechargeable batteries. I love them! So I just let them play with their coleman and stock maglites while I drop jaws with mine. (Can't wait for my DRY to come :P)