Damaged Fin after power supply failure

We had an accidental short between the positive and negative outputs of our power supply that was powering one of our Fins. After replacing the power supply we could not get the Fin to boot. When booting the Fin in MSD mode it enumerates as a 32.1 MB block storage device rather than the expected 8 GB. My best guess is the MMC was interrupted during a sensitive operation. Has anyone run into this before, and have you found a way to recover from this state?

[349024.872401] usb 3-2.7.7: new high-speed USB device number 30 using xhci_hcd
[349024.973035] usb 3-2.7.7: New USB device found, idVendor=0a5c, idProduct=0001
[349024.973037] usb 3-2.7.7: New USB device strings: Mfr=2, Product=1, SerialNumber=3
[349024.973038] usb 3-2.7.7: Product: Compute Module
[349024.973039] usb 3-2.7.7: Manufacturer: Raspberry Pi
[349024.973040] usb 3-2.7.7: SerialNumber: 257c76f6
[349024.973568] usb-storage 3-2.7.7:1.0: USB Mass Storage device detected
[349024.973755] scsi host6: usb-storage 3-2.7.7:1.0
[349026.004773] scsi 6:0:0:0: Direct-Access     RPi-MSD- 0001                  PQ: 0 ANSI: 2
[349026.005055] sd 6:0:0:0: Attached scsi generic sg3 type 0
[349026.005612] sd 6:0:0:0: [sdc] 62688 512-byte logical blocks: (32.1 MB/30.6 MiB)
[349026.005753] sd 6:0:0:0: [sdc] Write Protect is off
[349026.005754] sd 6:0:0:0: [sdc] Mode Sense: 0f 00 00 00
[349026.005878] sd 6:0:0:0: [sdc] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA
[349026.015551] sd 6:0:0:0: [sdc] Attached SCSI removable disk

Hello @aferm, we have seen a case where after power issues the eMMC reported 32MB storage. Unfortunately, we haven’t found a way to recover it to the original size. We are currently talking to the manufacturer to see if there is a way to get the devices back to the original state. I will keep this post updated when I have more news.
What type of power supply were you using when the short happened?


We were using a 12V battery backed solar system. The short was caused by an improperly insulated battery terminal coming into contact with our grounded metal enclosure.

I have the same issue, however I think I caused it by using the PiJuice hat.
The Fin wont respond (wont connect to Balena, no HDMI output), only the 5v, 3v3 and ACT light light up and etcher only detects 32.1MB of storage on the Fin
32GB model, no M.2 plugged in

Thanks for the details about your setup.
I’ve passed this to the Fin team and we will get back to you soon.

Kind regards,

@Holsty @aferm our warranty doesn’t cover issues caused by power supply failures, but we can offer to do a full investigation on those devices and see wether they can be fixed (and what the cost associated is in case it’s not under warranty). In order to do so, we would need the devices to be returned to our facilities. If that’s something you would like us to do, please send us an email to store@balena.io with the order number.