Hard drive failure, but is the rest working?

Hi,

I recently dug out my old iPod video 5.5G 80Gb.

The hard drive had failed so I put it aside some years ago.

Now I decided to fix it. I replaced the battery with a new one for starters.

No I want to get a new drive or SD adapter but before that I need to make sure the rest of it is working.

With the failed drive or even without it, the iPod boots and goes into the unhappy face screen, stays there for about 10 secs and then goes into Very Low Battery and turns off (battery is fully charged).

It is not recognized by iTunes.

I can enter both diagnostic mode and disk mode.

When in disc mode it will stay there no problem (that's how I charged it)

BUT when I connect it to a PC following happens:

Is show the Do Not Disconnect screen,

gets recognized by windows

but before iTunes recognizes it it reboots.

After a while iTunes recognizes that an iPod has been connected (a while ago),

says something about restore in a pop up message and on the background I see the iPod restore screen where the iPod is listed and it says Serial Number : n/a

This disappears after I click OK in the pop up message.

As I said its the same with either the failed drive or NO DRIVE AT ALL.

II'm not sure if the iPod should even be recognized without a hard drive installed so here's my question.

Is the behavior I described normal for a fully functional iPod without hard drive?

Should I order a new hard drive?

Thanks in advance!