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When I use the JTV guitar not connect to my POD HD 500x, the battery light flash for just 3 seconds and it doesn't work. I have recharged it for many hours, but it doesn't work. What is wrong?

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Do you know how to use a DVM (volt meter)?  If so, what voltage is the battery currently and what voltage is available at the charger contacts with it plugged into the wall wart?  

 

If you don't know how to measure voltages open a ticket with Line6 support.  

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jerseyboy  what should a fully charged battery read:   about 8.4  because mine read 8.3-8.4

 

Trying to figure out why the batteries are flatting after about 5 minutes.......   

 

I think I may have a short in the JVT.    Still trying to sort it out.   

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4.2V is lithium polymer/ion top charge voltage.  JTV pack uses 2 cells in series so 8.3-8.4V would indicate fully charged pack.  However, Lithium chemistry can be damaged and/or degrade over time.  The resting voltage level may appear fully charged but when actually powering something the chemistry can no longer provide any working Amperes to power a load.  Under load the voltage drops considerably.  

 

This condition is related to IR or internal resistance of the battery cells.  High IR indicates a cell which cannot deliver much if any power.  (Amps) 

 

Someone with RC modeling background will understand and recognize such battery behavior.  Pretty much same voltage chemistry parameters used by RC products.  Search youtube for Lipo IR testing.  Technically inclined folks can apply a known load and use calculations to determine IR of any battery chemistry cell.  

 

If I were testing JTV battery pack I’d start fully charged.  Next apply enough resistive load to pull about between 0.2-0.3A from the battery terminals.  

Apply for few seconds and if resting 8V dropped near or below 6V I would judge it to be a poor battery pack.  Essentially checking voltage drop under load.  

 

Could also measure pack voltage via wiring connections inside the guitar when powered up.  But probe the wrong spot or slip of a hand and things could quickly get messy.  

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Frankg111,... it may be a case of an intermittent connection, the battery box circuit

might be sending a false low battery signal to the processor board.

 

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8 hours ago, jerseyboy said:

4.2V is lithium polymer/ion top charge voltage.  JTV pack uses 2 cells in series so 8.3-8.4V would indicate fully charged pack.  However, Lithium chemistry can be damaged and/or degrade over time.  The resting voltage level may appear fully charged but when actually powering something the chemistry can no longer provide any working Amperes to power a load.  Under load the voltage drops considerably.  

 

This condition is related to IR or internal resistance of the battery cells.  High IR indicates a cell which cannot deliver much if any power.  (Amps) 

 

Someone with RC modeling background will understand and recognize such battery behavior.  Pretty much same voltage chemistry parameters used by RC products.  Search youtube for Lipo IR testing.  Technically inclined folks can apply a known load and use calculations to determine IR of any battery chemistry cell.  

 

If I were testing JTV battery pack I’d start fully charged.  Next apply enough resistive load to pull about between 0.2-0.3A from the battery terminals.  

Apply for few seconds and if resting 8V dropped near or below 6V I would judge it to be a poor battery pack.  Essentially checking voltage drop under load.  

 

Could also measure pack voltage via wiring connections inside the guitar when powered up.  But probe the wrong spot or slip of a hand and things could quickly get messy.  

This is the kind of response that makes me love this forum. You get people like @jerseyboy who clearly knows a lot about things we care about and is willing to share. Thank you!

 

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7 hours ago, psarkissian said:

Frankg111,... it may be a case of an intermittent connection, the battery box circuit

might be sending a false low battery signal to the processor board.

 

I have found there’s some sensitive in how the battery seats in the charger and the guitar. I had a case where I thought there was a charging problem, but the issue was I didn’t get the battery seated well enough in the charger.

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