Many people already know that if your iPod locks up you can reset it by holding the middle button and "menu" down until it reboots. This works for the occasional lock-up but what do you do when the occasional becomes common?
You try out the iPod "Diag Boot"!
By holding down the center button and the previous "|<<" button you will enter a diagnostic system. You have to hold down these buttons AFTER doing a reboot.
I have run the automatic diagnostics and this is my result:
Failure Code: 702 with 11 fails
Hmmm... Looks like some of my problems may be due to a bad iPod?
The test then begins a series of interactive tests to test the buttons, wheel, etc... I got as far as the "Accessorize Test" when it asked me to "Please plug FW." I'm guessing it wants to test the port at the bottom of the iPod but I'm not anywhere near my cable so I'll have to wait on that.
If you choose to try the manual tests you will find a large number of things you can check. You can even find out the current temperature of the hard disk!