# Troubledshoot - CREE XM-L T6 LED 1600Lm Headlamp Bike Light Lamp



## djonesax (Jul 21, 2008)

HI,

I have this light and with the wide angle lens, it works well as far as light it concerned. I have an issue with it shutting off on me though. The first time I used it, on a full charge, it blinked off after less than an hour and would not turn back on. The second time I used it, it worked fine. The third time, it blinked off right after turning it on. I cant return it now, it's been too long. How can I tell if it is the battery or the light itself that is the problem? I can make a new batter back for it if thats the issue.

CREE XM-L T6 LED 1600Lm Headlamp Bike Light Lamp | eBay

Features
2 In 1 : Headlamp or Bike Lamp ,Can be used as Headlamp or Bicycie Light
Light bulb type: U.S.A CREE XM-L T6 LED 
Output bright : 1200lm~1600lm (Max 1600 lumens [lm] )
Internal wiring applies the high efficient booster circuit, working voltage is wide and can utilize the batteries in the largest extent.
Waterproofing design
Aluminum alloy casing
Aluminum alloy reflector
3 Light Modes: Strong Brightness / Normal Brightness / Flashing
100v-240v AC Charger ( LED indication for Power On / Charging / Full charge )
Model of Battery required: 1 x 8.4v 6400mAh Battery Pack
Dimension : 43mm

Thanks,

David


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## Rich_SC (Oct 10, 2009)

I'd say you bought a very cheap chinese light. Find another 7.4v battery and see if it works.


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## brad72 (Jun 12, 2009)

Hi David. Do you have any tools like a multimeter that you can test with? It sounds like a battery problem or a loose wire somewhere or a dry solder join.


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## Goldigger (Nov 6, 2009)

I just looked up this light on ebay..
Where do they get the figures from, 1200-1600lumens from a single T6 XM-l? 

Still $50 including shipping dam cheap


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## mattthemuppet (Jul 16, 2004)

yep, unless it's a simple resoldering job that he can do himself he'd be better off throwing it away and getting another one.

Sounds like a wonky battery PCB to me


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## djonesax (Jul 21, 2008)

brad72 said:


> Hi David. Do you have any tools like a multimeter that you can test with? It sounds like a battery problem or a loose wire somewhere or a dry solder join.


Yes, I do.


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## djonesax (Jul 21, 2008)

I bought it as a backup to my Marwi P7 Mod because the switch was failing and I wanted to make sure I had a light while waiting on a new switch. I was very impressed with the output. It's brighter than my P7 but it has a spot. Same flood, but with a spot which was distracting so I ordered a wide angle lens and it made it better. Just jave to figure out whats wrong with it


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## djonesax (Jul 21, 2008)

mattthemuppet said:


> Sounds like a wonky battery PCB to me


thats exactly what I thought but wasnt sure how to test that. Also unless the PCB is very small it doesnt look like there is room for it in the pack. Could be the driver in the light too I suppose.

Also the pack says 8.2v but 18650 are 3.6v with a 4.2v peak at full charge right? Maybe they PCB is for 8.4v and cutting off too early. It goes from super bright to nothing.

I have an extra 4 cell battery holder from digikey. Maybe i'll solder a 7.6v/8.4v pack together with no PCB and see how it works.

David


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## Ofroad'bent (Jul 10, 2010)

It looks like the notorious older Magicshine battery. Over-stated battery capacity and overstated lumens aside, it's not a big deal to replace the PCM. 

Here's one on eBay (Item # 220814378050 - link not allowed here)

Ktronic here on the DIY forum also sells PCMs.


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## mattthemuppet (Jul 16, 2004)

you can't easily test the PCB for faults, so it's easier just to test the lighthead with another battery. If the second battery solves the problem, it's probably the PCB in the original pack. I would recommend a decent PCB (Ktronic or Batteryspace) though - you don't want to accidentally overdischarge your new battery and ruin it. PCBs also protect against shorting and overdischarge, plus the fancier ones can balance the cells in your pack too.


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## diviy (Sep 22, 2011)

I got the same problem charged battery and light not working battery only showing 2.4v after a charge got another light but the plug is a different size whats the pcm for the 4 pack batterys thats what I, have


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