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kandrey89
USA
4 Posts |
 Posted - 07/14/2025 : 12:49:21
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Hello,
I have a GMC320 Plus V4 that I haven't used in like 5 years.
I fully expected the 14500 battery to be dead, however I plugged in the USB and the unit started to infinitely restart. Why?
Next I tried removing the battery and the unit started to scream/emit noise. Had to unplug from USB. Unit only makes noise without battery plugged in and with USB power. Unit continues to power cycle on USB power.
Any help please... |
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| Reply #1
Kaninbjerget
Denmark
22 Posts |
Posted - 07/15/2025 : 11:56:01
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Yes the battery is 100% dead and attempting to recharge it for a lengthy time may even be risky to cells in that state. In some constructions the battery is used for voltage stabilization when plugged in. That seems the case with both your V4 and my newer 320S which I keep without battery in prepping stash. Just tryed pluggin in USB without battery and does the exact same thing. Putting in a battery everything is back to normal.
You have two options.
1. Get a new 14500 LiIon cell. They're quite cheap but please choose a well known brand and not some random junk that risk catching fire.
2. Get a 3,6 v AA size Lithium Thionyl single use battery. Very important! Efter putting the battery in go to the battery menu (Others - Battery - Battery Type) and select Non Rechargeable. Then you can safely power it using USB and the battery is purely backup and for time keeping.
I have lithium thionyl cells in my prepping stash because when left outside device they have 20+ years shelf life - in real life probably even close to 40 without loosing too much of the original capacity - but must be out of device as clock and cirquit to listen for power keypress is running when battery is installed. Should there be an unfortunate event where I really need my geiger I'm confident I can power it for a good amount of time (turn off backlight). |
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| Reply #2
EmfDev
2349 Posts |
Posted - 07/16/2025 : 13:21:03
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yeah check to see if the battery is still good because if it is bad, it can heat up very fast.
also for the restarting, let it restart until it fixes itself. once it is good, you need to do a factory reset asap. |
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| Reply #3
kandrey89
USA
4 Posts |
Posted - 07/16/2025 : 15:03:26
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How do I do a factory reset?
Perhaps I should also do a firmware update after, I tried looking on the website but couldn't find it. |
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| Reply #4
kandrey89
USA
4 Posts |
Posted - 07/17/2025 : 11:31:15
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| Replaced 14500 3.7V battery, plugged in USB, sound/noise is gone, however it's boot cycling ad-infinitum, what's the course of action if it doesn't stop cycling? |
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| Reply #5
EmfDev
2349 Posts |
Posted - 07/21/2025 : 12:36:23
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| just wait and pray till it boots up. factory reset can be found on Main Menu -> Init setup -> Factory Reset. |
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| Reply #6
Kaninbjerget
Denmark
22 Posts |
Posted - 07/23/2025 : 22:49:38
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Still got an issue with rebooting?
If you have something else to charge the 14500 cell in then try that. What is the voltage measured on the 14500? What I'm suspecting is it might have low charge but without measuring we don't know. On the other hand I tried some cells I have laying around that was about 2,8v or so. They still showed as 5% available (it's an approximation, the 300S doesn't do energy in/out to give exact amount). At 2,8v I'd say they were completely flat for any use (2,2v is the very lowest you should use LiIons as they risk becomming unstable - especially if stored for some time). I tought they had more than that and no protection circuit self discharge should be very low but apparently not. But hey they are cheap junk cell I safety wise really don't recommend anybody to use - they were in another device I bought so not a concious buy. |
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| Reply #7
kandrey89
USA
4 Posts |
Posted - 07/25/2025 : 22:52:52
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After a few hours, it stopped cycling and booted. Can use it OK now. New 3.7V 14500 rechargable batteries worked fine and charged fine inside device.
Thank you |
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Topic |
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GMC320 Plus Making Buzzing Noise, Power Cycling
