Prius 2 HU and 750Gb WD Elements HD.

So I'm writing to document and add to the collective knowledge base my experiences with trying to use my 2013 Prius 2 stock head unit with an external storage drive, a 750Gb Western Digital Element USB 3.0/2.0 external hard drive.

I chose an external storage drive instead of the more-commonly used USB flash drive for two reasons:

1) I like to rip my music at maximum bitrates for maximum fidelity = large files. Yes, is is arguable whether this is of any point in a noisy car environment. But that is how I rip them for all uses, and I don't want to cross-encode a set of stuff specifically for car use.

2) I'm a little wary of the longevity of flash drives. Just had too many fail on me.

So far I can confirm:

1) The only file system the HU will use is FAT32 (FAT16 was not explored as it is way archaic). exFAT is tolerated in other partition(s) that may co-exist on the physical drive (but you will not have access to them), while presence of any NTFS partitions will just flummox the HU and give you nothing at all from the entire physical drive.

2) The HU will only give you access to one partition on your physical drive. It doesn't give you any means to switch. I do not know what rules it employs to select which one, but the point is: you must keep all your music on one FAT32 partition. Making it the only FAT32 partition ensures no issues. (Besides, who wants a general-purpose FAT32 partition instead of the more-advanced file systems available these days anyways?)

As of right now I have the drive partitioned as a 32gb FAT32 + 666Gb exFAT. The HU recognizes the FAT32 partition and utilizes it without problems, while ignoring the exFAT partition that I intend to use for non-music data.

My next experiment will involve expanding the FAT32 partition (FAT32 is theoretically good to 2Tb, although Windows disk management will only allow you to make a partition no bigger than 32Gb; there exists programs that *will* let you do that) to 64Gb and larger.

 

Yes, I have had no problems listening to songs and having the correct album information to show up. I have not tried playing videos, and probably won't.

I am encoding in WMA maximum bit rate (300+ VBR) through Windows Media Player in Windows 8.1.

 

Update: too good to be true... partially.

This morning, I noticed that the HU started to exhibit a hang-up. With the drive plugged-in, the HU would hang in trying to resolve the drive upon start of the car. This was rectifiable by unplugging the drive, and re-plugging the drive back in while the car/HU was already on, after which it would detect the correct partition and allow music to play normally. This was a repeatable phenomenon.

So I nuked the exFAT partition.

Nuking the exFAT partition allowed the HU to recognize the drive upon car start-up, as it seemed to have done without issue yesterday in the presence of the exFAT partition.

I then extended the FAT32 partition to the whole 750Gb. No issues.

I will monitor to see if this continues to work correctly (i.e. recognizes the drive) on car/HU start-up.

 

Phil Wheeler: Yup. See prior posts about file system specifics.

All: It needs to be noted that I'm not sure if the HU is reading my folder hierarchy or generating its own catalog off of the tags in the individual files. Basically I just copied straight off of the "Music" folder of my Windows PC. Which is to say that they are in the portable hard drive like:

A "Music" folder in the root directory (doesn't seem to matter if this is here, or if the next level sits in the root directory)

Artist name subdirectory one level in. The HU seems to ignore this, to my chagrin.

Album name subdirectory next level in. The HU is either acknowledging this, or is generating its own catalog from file tags.

Song files. I'm using WMA 300+ VBR. I don't suspect MP3 will be much different.

madmike23: The HU organizes my songs into albums, and the files of that album are contained in that. So I scroll through the contents of each individual album, and up one level I get to scroll through the names of the albums. Unfortunately, I have not been able to find a way yet for the HU to recognize the organization of albums by artists. Scrolling is via touchscreen and is not fun. I have not exhausted the possibilities, so there might exist an easier way, who knows.

I can use the steering wheel controls to hop from song-to-song (audio direction buttons), or change albums (hold down the audio direction buttons until a beep is heard).

 

I just think of it as installing an infinite-capacity (effectively, for me) CD changer for $32.