mj818 - changing modes?

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mudcow007
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mj818 - changing modes?

Postby mudcow007 » Fri Nov 09, 2012 12:07 pm

right i got a MagicShine MJ818 on the ars* end of my bike

for the past week it has been changing flashing modes randomly

the only time the mode doesn't change is when the light is on "eye burning" steady fixed light - but i dunno how long my battery pack will last on this mode

any ideas

the bezel doesn't seem to be moving as i'm riding along or anything?
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fossyant
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Re: mj818 - changing modes?

Postby fossyant » Fri Nov 09, 2012 12:43 pm

You haven't got a broken wire ?

Mine sometimes does it, and it can be that you haven't turned the bezel far enough past the magnetic sensor - i.e. if it's close it could cause a mode change with vibration.

I use mine on steady most, and are powered by 6x AA packs I home brewed so only have 2500mah. Work for a good 6 plus hours on steady.

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mudcow007
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Re: mj818 - changing modes?

Postby mudcow007 » Fri Nov 09, 2012 13:27 pm

dont think i broke any wires....(hopefully)

i wil try an figure out where it changes the sequences an adjust.

it keeps defaulting back to the flash that has a massive pause between flashes grr
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DaxPlusPlus
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Re: mj818 - changing modes?

Postby DaxPlusPlus » Fri Nov 01, 2013 13:09 pm

Did you get to the bottom of this? I have two of these on the back of my bike and neither of them will stay constantly on - they randomly switch modes.

The fact that both of them have started doing it points to something common to both of them .. and that's the batteries (they share via a y splitter cable .. long story). I just don't understand how it could be the batteries .. they seem to be holding their charge fine.

Thanks.
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Slowbike
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Re: mj818 - changing modes?

Postby Slowbike » Fri Nov 01, 2013 13:14 pm

I believe it's to do with short interruption to power - I had similar issue with my UltraFire torch - mine was fixed by shimming the battery with some paper to stop it breaking contact inside the housing.

So for an external battery pack you need to check that any and all connections are secure and sound.

TGOTB
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Re: mj818 - changing modes?

Postby TGOTB » Fri Nov 01, 2013 13:16 pm

Possibly a connector issue, momentarily breaking contact when you go over a bump? Check the connectors themselves, and also the cable where it goes into the back of the connector.

I had connector issues with my MagicShines and ended up removing the connectors completely and soldering everything together; the only connector remaining in the system was one to plug the charger into...
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Sharkyssurfers
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Re: mj818 - changing modes?

Postby Sharkyssurfers » Fri Nov 01, 2013 13:17 pm

when i had two they lasted a month each before i got a refund, the problem with mine was the twisting action actually cut through the wires. I have one of them big water bottle batteries that i now use with my big 2000 lumens jobby, when i spoke to magicshine a few weeks back they did say they have improved the rear light, so might invest in one.
Sorry its not me it's the bike ;o)

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DaxPlusPlus
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Re: mj818 - changing modes?

Postby DaxPlusPlus » Fri Nov 01, 2013 13:46 pm

Thanks for the quick feedback :-)

I'll look at the connectors.

Checking the batteries may be an issue as I think they may be sealed up but I'll have a go.

And yep I know about the eating the wires design flaw. One of mine self destructed a year or two ago - i soldered it back together. This design flaw is "fixed" by _always_ turning the bevel one way. Has worked for me ever since (and I run them during the day too so they get a lot of use) but I'll have a look at the state of the connectors over the weekend just in case.

Apart from this I love them .. last ages and very bright.
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fossyant
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Re: mj818 - changing modes?

Postby fossyant » Fri Nov 01, 2013 13:57 pm

I've switched to the c&b seen rear lights now. Still got the magicshines, but the mode changing was a pain.

The c&b seen lights are seriously bright. I run 2 from a home made 18650 pack, but they still eat charge at a fast rate.

TGOTB
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Re: mj818 - changing modes?

Postby TGOTB » Fri Nov 01, 2013 13:57 pm

DaxPlusPlus wrote:Checking the batteries may be an issue as I think they may be sealed up but I'll have a go.

The bit inside the seal is all soldered, so less likely to be causing an issue (but check the wire where it exits the package.
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mudcow007
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Re: mj818 - changing modes?

Postby mudcow007 » Fri Nov 01, 2013 15:39 pm

nope i didnt get the bottom of it to be honest

i have kinda retired the light as it was getting royally onto ones boobs, the way it would randomly go off :cry:

so any suggestions to suit it would be bloody marvellous
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Slowbike
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Re: mj818 - changing modes?

Postby Slowbike » Fri Nov 01, 2013 15:49 pm

mudcow007 wrote:so any suggestions to suit it would be bloody marvellous


It's not a complicated light - as said above, changing modes is down to a quick interruption to power source - this is how the button works. So it's just a case of eliminating the cheap bits (connectors & wires) and then when that doesn't work it's likely to be the circuit board or the even light itself...at which point it's probably not worth going much further unless you're interested in circuit boards!

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mudcow007
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Re: mj818 - changing modes?

Postby mudcow007 » Fri Nov 01, 2013 15:57 pm

Righto, i will refit it to the bike an see how its behaving.

im sure someone will have a breakdown guide to how you take it to bits

cheers
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DaxPlusPlus
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Re: mj818 - changing modes?

Postby DaxPlusPlus » Fri Nov 01, 2013 16:00 pm

http://www.youtube.com/watch?v=GdI_vUiN38I- here you go 3 videos that take you through it 8)
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Slowbike
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Re: mj818 - changing modes?

Postby Slowbike » Fri Nov 01, 2013 16:00 pm

mudcow007 wrote:im sure someone will have a breakdown guide to how you take it to bits

Hammer?

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itboffin
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Re: mj818 - changing modes?

Postby itboffin » Mon Nov 04, 2013 19:53 pm

Slowbike wrote:I believe it's to do with short interruption to power - I had similar issue with my UltraFire torch - mine was fixed by shimming the battery with some paper to stop it breaking contact inside the housing.

So for an external battery pack you need to check that any and all connections are secure and sound.


+1 its usually this, most of the 16500 sized batteries are slightly different in size, i wrap gaff tape a couple of times around each once that ensures a snug fit.
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DaxPlusPlus
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Re: mj818 - changing modes?

Postby DaxPlusPlus » Thu Nov 14, 2013 22:18 pm

Bit of an update.

I don't think it's lose connections .. the mode changing just does not tie in with connections being disturbed.

For a day or so I wondered if it was due to water getting into the light units (and there is still a very slight chance that this is the cause).

However chief suspect at the moment is that the batteries themselves are dying .. the mode changing gets worse the longer I leave it between charges. I remember reading somewhere that the battery backs have a very simplistic design and that it can lead to uneven discharging of the batteries.

I will look into this and see if I can find out more.
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Slowbike
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Re: mj818 - changing modes?

Postby Slowbike » Fri Nov 15, 2013 09:37 am

Have you sat it on the dining room table, turned on the lights and left it ...

All the time they're fitted to the bike you could be on loose connections ... putting the lights in a stable place with no physical movement will test that (although it won't totally help if the cables are heating up a bit ... !)

good luck ... :)

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DaxPlusPlus
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Re: mj818 - changing modes?

Postby DaxPlusPlus » Fri Nov 15, 2013 09:47 am

I like your thinking but I'm not sure how hot the leds get and whether they might burn out .. I know with the cheaper torches that's a real possibility.
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Slowbike
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Re: mj818 - changing modes?

Postby Slowbike » Fri Nov 15, 2013 10:25 am

really? I wouldn't think they'd get hot enough sat on the dining room table - unless you have the heating cranked up to 50°C - but ok, don't sit them on the dining room table - put them on the patio table ... outside ...


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