iPod not turning on (SOLVED)

[MXIIA]

I've tried every possible button combination, then I tried them all while plugged into the computer. I even put it on my iHome and it didn't even show the apple screen. I just installed RockBox yesterday.
It is an iPod Nano, 1st Gen 2GB. It worked fine until I tried to load the a demo plugin.

[soap]

Either the battery is very low, or the iPod (wrongly?) believes the battery is very low.

Toggle the hold switch to on (red) and back off (white) again, then press and hold Menu and Select (center button) for up to sixty seconds.
If this does not boot your iPod you need to plug it into a known good charging solution for 12 hours and then (and only then) try again.

[MXIIA]

Yea, I just jiggled the hold switch on and off for 10 seconds, then hit MENU and SELECT, the battery is at 90% with 5 minutes left  , I am charging it now.

[soap]

Yea, I just jiggled the hold switch on and off for 10 seconds, then hit MENU and SELECT

Glad it worked for you, but for future reference there is no need to jiggle the fragile hold switch.  Toggling it once is all that is needed.

[SindreD]

I think I can continue this topic as I have the same kind of troubles.

I used the function wake-up alarm, but it didn't work because I don't think I had enough battery left, so I went to charge it at my computer the next morning. Unfortunately, the computer didn't recognize it and I couldn't get it to boot up either.

The only lifesigns I could get was the battery with exlamation point after restarting the ipod undocked.

Battery with exclamation point:


When docked in the computer and restarting, the monochrome low battery is displayed.

Monochrome low battery:


If I only dock it, without restarting, I won't get any kind of lifesigns:(

I supposed that when docked, the ipod was charging and would soon have enough battery to function normal, although now it have been in this mode for at least six hours, and the ipod still behaves the same way. So, I am a bit worried and do not have any clue what I do now.

EDIT: It would be nice if a moderator could edit the topic, ie. removing "SOLVED". Thanks.

[soap]

EDIT: It would be nice if a moderator could edit the topic, ie. removing "SOLVED". Thanks.

My original reply (post #2 in this thread) also applies to you.
The original poster's problem was solved, and I'll bet my right hand yours will be as well if you follow the advice in this thread.

[SindreD]

Maybe I have been a bit unclear. When saying "restarting", I have gone through the steps according to your post #2.

[soap]

You (by your own admission) haven't left the iPod alone on charge for 12 hours.
A deeply discharged battery can take a long time to recharge.
If, after at least 12 hours of charging, your iPod will not boot past the low-battery warning try restarting while plugged in, and try charging overnight again.
Also, start to suspect your charging cable or USB port is not providing the power you assume it is.

This procedure will work unless your battery is permanently dead.

[SindreD]

Have I understood it right that if you have a battery that is deeply discharged the charging circuit won't charge the battery as fast as if the battery only was normally discharged?

I will try to let the ipod charge for another day and follow your instructions and hope that it comes back to life.

Also, I am wondering if it is necessary to have the low battery-icon displayed when plugged in to have the ipod charging or would the ipod charge if the display is off as long as it is docked?

[bluebrother]

Let me try to explain it in a not-so-technical way:
during normal operation, your battery has some basic power in it. Let's say we need at least 3.5V to power up, and a completely filled battery has 4.2V (haven't checked the exact values but it's something in that range). Now imagine your battery being completely flat -- i.e. having the power of 0V. This means you need to fill up to those 3.5V until your Ipod can do anything at all. Now consider that filling up like 0.1V needs the same time, regardless if your battery was at 0V or at 4.0V when starting charging you'll figure that charging from a flat battery takes *much* longer than from the usual "empty" battery.

Don't take the mentioned values itself literally (though I don't think I'm too much off the reality), but that should at least explain the basic reasons behind it.

[Llorean]

Just to clarify, if a Lithium based battery gets too low it can't really be recharged at all. The key point in bluebrother's post though is that "there's a line, and you can be below it instead of always starting from the line."

Think of your battery as being well below "0%" in Rockbox, and needing to get up *to* "0%" before you can start using it at all. A flat battery isn't always "0%", sometimes it's much less.

[SindreD]

From Wikipedia:
"Li-ion batteries can even go into a state that is known as deep discharge. At this point, the battery may take a very long time to recharge. For example, a laptop battery that normally charges fully in 3 hours may take up to 42 hours to recharge. Or the deep discharge state may be so severe that the battery will never come back to life. Deep discharging only takes place when products with rechargeable batteries are left unused for extended periods of time (often 2 or more years) or when they are fully discharged so often that they can no longer hold a charge."

If I have understood bluebrother's explanation the right way, he means that the voltage will rise linear with a constant voltage/time=constant ratio, although this would contradict the function of electrochemical cells. I am not very familiar with the lithium-ion cells but from what I could understand from the explanation at wikipedia, the principle is the same as other electrochemical cells with two half-cells.

Then there is the possibility of deep discharging. Now, the circuit that charges and discharges the battery, will normally prevent the battery from getting deeply discharged, and will therefore prevent permanent damage. As quoted from the text above, this can only happen when the battery is left unused from extended periods of time, because of the circuit that drains small amount of power. I therefore have no reason to believe that my battery suffers from this.

Whenever I have used the ipod before, I have never encountered any behaviour similar to this. The ipod has just shut down, and immediately began communicating with the computer when charging. I still is a mystery to me why the ipod got into this state...

[Chronon]

You should appreciate that the internal resistance of an electrochemical cell generally depends upon the charge state.  At low charge states the internal resistance will be much higher and this will dramatically reduce the effective amount of current available for charging at a given charger voltage.  This will lead to much longer charging times for lower states of charge. 

Just be patient and let your iPod charge.  It will eventually wake up and boot properly when the battery has enough charge.  I have had this happen on a few occasions with the two different iPods that I have owned.

[Llorean]

Notably, we've seen reports of this with non-Rockbox iPods too. It's a common enough thing that happens to these devices, and we're not sure why.

[SindreD]

I guess I'll just have to wait and see then. Thanks for explaining!