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Old 02-24-10, 09:40 PM   #1
macdonwald
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P7 going bonkers in the cold

At least I think it's the cold that's to blame. I've had my 8-mode P7 for about a year and this winter it started behaving very erratically--constantly changing modes, shutting off, then starting back up, flickering, etc. It's imperfectly correlated to going over bumps. I'm in Philly so by cold I just mean 15-30F.

Any ideas for what I can do to mitigate this?
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Old 02-25-10, 12:01 AM   #2
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Electronics can change their behavior with temperature changes but I'd guess you have an intermittant contact somewhere. If you have access to a soldering iron try touching up all the solder joints. Also check any spring loaded parts to make sure they are making good contact.
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Old 02-25-10, 09:19 AM   #3
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+1, I'd look for a bad contact, or a bad switch. That's the most likely effect of cold weather, metal and plastic shrinks, contacts pull apart, plastic and rubber gets stiff. Try just tightening up the threaded components inside.
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Old 02-25-10, 10:29 AM   #4
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Thanks for the replies. I definitely don't have access to a soldering iron and wouldn't really know where to begin even if I did. But ItsJustMe, what do you mean by "tightening up the threaded components inside"?

Is there anything I could do on the know-how order of sticking a wad of aluminum foil in there to stabilize things?
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Old 02-25-10, 11:21 AM   #5
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Often flashlights are held together by threaded components, and if they rattle loose, you get intermittent connections.

Look inside to see if there are threads on the inside with a piece of metal, perhaps with a couple of slots on the side, that looks like it's screwed into the threads. Get hold of those slots with something (ideally a spanner but whatever you've got) and see if you can tighten it.
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Old 02-25-10, 08:26 PM   #6
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I had the same problem macdonwald. Like ItsJustMe said make sure everything is tightend.

MY problem I found out was a faulty tailcap (at least that's what I think it was). Depending on where you bought it you may be able to get a replacement. I found out I really didn't need a 5 mode P7 and bought a 2 mode instead. Now if I hit a bump to hard it doesn't start cycling through the different modes, just one click and i'm back at Hi.
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Old 02-26-10, 12:59 AM   #7
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My DX light did the same. It's due to a bad contact, thanks to the poor quality of these lights. I replaced mine with a quality light from Shining Beam and haven't looked back.
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