How to replace an iPod 4th Gen hard drive with a Compact Flash Card

This approach is much better than replacing your drive with another hard drive because CompactFlash cards are more robust than physical hard drives which eventually break or wear out and are sensitive to dropping.  You will lose some storage capacity but presumably, if your hard drive has failed, you have the choice to either buy a new iPod, buy a new hard drive or replace the drive with compact flash. The iPod Nanos, shuffles and iTouch all use flash memory because they are more robust to failure.
 
This fix works on both all the 4th gen types including photo.  You will need a particular interface adapter and a compact flash card.  I have purchased several different adapters on Ebay, and this is the only one that I have got to work (and it's only about $4 including shipping).  If you do not see listings below, put  the phrase
 
compact flash ipod adapter
4th gen compact flash adapter
in our search box.  Find a listing that looks like this:
 
Compact-Flash CF Card to Toshiba IPod 1.8
 
There are 2 minor mods (takes just a few seconds) to make the adapter work (described in this article).

The Compact Flash card must have full ATA compatibility in order to work. CF cards are supposed to work since they are designed to be ATA compatible, but SD cards in general will not work. Cards with less than 2GB of storage are not likely to work. Ones which have been shown to work are:

Sandisk Ultra II cards (I used 8 GB)
Sandisk ultra III 
RiDATA Pro 8GB Compact Flash (CF) Flash Card Model CFR8G-SILV
Transcend CF cards
Kingston 4gb cf 45X elite pro card (not all Kingston cards work)
Sandisk ultra III 4gb
Peak Xtreme
A-Data CF cards
8GB Memory Corp Pro 133X CF card
16gb Peak
Lexar 2GB CF Platium II 80x


Open up your iPod following this guide:
http://www.ifixit.com/Guide/Repair/iPod-4th-Generation-or-Photo-Hard-Drive/391/1
Following these instructions, you will get to the end where you remove the drive, don't remove the cable if you can help it. You will want to keep the Molex connector attached to the board (if you do remove it, it can be put back in).
 
You will need to do 3 things to make this work: 
1.The cable in your iPod has a plastic keying pin at the end which will keep your Compact Flash from seating.  Cut this little plastic pin tab off with a pair of wire cutters. 
2. The adapter will have a Master-Slave thing that is 2 small pins which stick up from the board (far left black post in the picture above).  This will distort the iPod when you go to close it up.  Take the shorting cap (plastic) off (or at least lift it partially so you can bend the pins).  Bend the pins over so they do not stick straight up-does not have to be close to the board.  Put the plastic shorting cap back on.  On the opposite side of the board, put a piece of rubber (like that which surrounds the original drive) under the pins that poke through.  These pins would short something out underneath.  This thing seems useless. I don't know what it's for.
3.  There are less pins in the iPod connector than there are in the Compact Flash adapter.  Position the flash adapter to fill the pins near the stub you broke off.  (there is nothing to cut here, just need to position the adapter correctly with respect to the connector)
 
There will be many pins protruding out of the other side of the adapter, this is where you will put the Compact Flash card. The card will be facing you.  You should put a glue dot or double sticky tape on the back side of the adapter onto the battery to keep it from banging around.

After the CF is installed and your iPod is closed back up again, you can connect the iPod to your Mac/PC which has iTunes on it  and hit restore to install new firmware to the iPod (if you plug it into the wall first, you will see the folder icon which is expected). After new firmware loads, you need to connect the iPod to an external power supply (this is always the case, not just for this repair). If you don't have your wall charger anymore (or you never had one) you can also use a car charger. The point is that you need a constant/higher current source than your USB port provides in order to burn the flash memory with the new firmware. You can also use the USB port on a PlayStation 2, and in some cases, the USB port on a digital picture frame!

If iTunes does not see your iPod, you need to use your computer to format the drive (to FAT32 if the CF card is 4GB or larger, to FAT16 if it is smaller than 4GB). Then try iTunes again. I sometimes format the card by itself before putting it in the iPod.
 
With a compact flash and a new battery, your iPod should run much longer than it did before.  You can use any size Compact Flash, 8 GB is a size which is not too expensive, and will hold quite a bit of music.
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