[Motorola Droid 4] feretio:
Long story short, my Droid 4 wound up submerged in my dogs water bowl. Of course, I immediately dried it off as much as possible, tried to power it off with the Vol-Down + Power button, took out the SD & SIM cards, and stick it in a bowl of rice with a monster dessicate bag. Since the battery on the Droid 4 is not [easily] removable, I didn't have much hope.

The phone was running JB and was rooted. However, it was a few months since my last backup (MyBackup Pro) so there was some data I really wanted to retrieve from the internal storage (some app data from /sdcard and my SMS/MMS from /data). After a few days, I plugged it into my laptop to see what would happen. I left it there for a few hours to charge.

The phone went through various stages of odd behavior (including a solid green led) but eventually, it seemed to boot. I could sort of tell when the LED started blinking like it had notifications. Eventually, it would even make a notification tone as well. The final clue was when I pressed the power button (as in turning on the display to unlock) and the menu/home/back/search buttons illuminated. I pulled out the keyboard and that illuminated as well. Note that these various signs of life had come over the course of a few days.

There was still nothing on the screen. Based on touch (and my spare Droid 4), I could feel the haptic feedback of the unlock slider and figured out that I could unlock the phone by using the physical keyboard to type in my password. At that point, I couldn't figure out what else the phone was doing because the only haptic feedback I was getting was from the menu/home/back/search buttons. However, this seemed to be a telltale sign that I had gotten the phone unlocked.

To my immense elation, I was presented with a device to mount when I plugged the phone into my linux box and it mounted! This would be internal /sdcard mount point.

Here's what I saw in the system logs:

Aug 23 06:49:45 mylaptop kernel: usb 1-1.2: new high-speed USB device number 89 using ehci-pci

Aug 23 06:49:45 mylaptop kernel: usb 1-1.2: New USB device found, idVendor=22b8, idProduct=4371

Aug 23 06:49:45 mylaptop kernel: usb 1-1.2: New USB device strings: Mfr=2, Product=3, SerialNumber=4

Aug 23 06:49:45 mylaptop kernel: usb 1-1.2: Product: XT894

Aug 23 06:49:45 mylaptop kernel: usb 1-1.2: Manufacturer: Motorola

Aug 23 06:49:45 mylaptop kernel: usb 1-1.2: SerialNumber: XXXXXXXXXXXX (real serial number redacted)

Aug 23 06:49:45 mylaptop kernel: scsi203 : usb-storage 1-1.2:1.0

Aug 23 06:49:45 mylaptop mtp-probe[24197]: checking bus 1, device 89: "/sys/devices/pci0000:00/0000:00:1a.0/usb1/1-1/1-1.2"

Aug 23 06:49:45 mylaptop mtp-probe[24197]: bus: 1, device: 89 was not an MTP device

Aug 23 06:49:46 mylaptop kernel: scsi 203:0:0:0: Direct-Access Motorola XT894 0000 PQ: 0 ANSI: 2

Aug 23 06:49:46 mylaptop kernel: sd 203:0:0:0: Attached scsi generic sg2 type 0

Aug 23 06:49:46 mylaptop kernel: scsi 203:0:0:1: Direct-Access Motorola XT894 0000 PQ: 0 ANSI: 2

Aug 23 06:49:46 mylaptop kernel: sd 203:0:0:1: Attached scsi generic sg3 type 0

Aug 23 06:49:46 mylaptop kernel: scsi 203:0:0:2: CD-ROM Motorola XT894 0000 PQ: 0 ANSI: 2

Aug 23 06:49:47 mylaptop kernel: sr1: scsi-1 drive

Aug 23 06:49:47 mylaptop kernel: sr 203:0:0:2: Attached scsi CD-ROM sr1

Aug 23 06:49:47 mylaptop kernel: sr 203:0:0:2: Attached scsi generic sg4 type 5

Aug 23 06:49:47 mylaptop kernel: sd 203:0:0:0: [sdb] Attached SCSI removable disk

Aug 23 06:49:47 mylaptop kernel: sd 203:0:0:1: [sdc] Attached SCSI removable disk

Aug 23 06:49:59 mylaptop kernel: sd 203:0:0:0: [sdb] 16803584 512-byte logical blocks: (8.60 GB/8.01 GiB)

Aug 23 06:49:59 mylaptop kernel: sd 203:0:0:0: [sdb] Write cache: enabled, read cache: enabled, doesn't support DPO or FUA

Aug 23 06:49:59 mylaptop kernel: sdb:

I mounted /dev/sdb and did a full backup and was able to access the app backup files that weren't saved to my MicroSD card (which wasn't damaged). For those unaware, the /dev/sr1 cdrom-like device contains the Motorola software for MS Windows.

The next step was to see if I could access the root file system to recover my SMS/MMS and other phone data. I already had the android toolkit installed but unfortunately, "adb devices" wouldn't show my device, presumably because I must have turned debugging off at some point. I tried using my spare Droid 4 to try and turn it on but to no avail. I returned to my research on other possible methods of getting debug enabled.

Here's the part that some people in the same position (nothing on the screen but some haptic feedback) might find very useful. A few days later, my morning alarm went off (Alarm Clock Extreme). Just before I touched the blank screen to turn off the alarm, I caught a very very very faint glimpse of the time. When the alarm goes off, the screen Alarm Clock Extreme presents is mostly dark with the clock displayed in large light-colored numbers. I realized that the only problem was that the backlight was shot.

I waited it was dark outside, dimmed the lights in my office and shined a bright flashlight at an angle at the screen. At first I didn't see anything until I removed the beat up, fingerprint covered screen protector. It was hard to see but I could indeed see everything on the screen! I had to use a cloth when touching the screen because the slightest finger smudges would render it impossible to see but I was able to get into the settings, disable the lock screen (so I didn't have to worry about logging in) and turned on USB debugging. Finally, I was able to see the device with adb! I ran "adb shell" and did a full backup of the root file system with tar, writing the tarball to /sdcard (sans the /storage partition), then copied the tarball to my laptop with adb pull.

A few other notes I found in my research:

o When trying to mount the internal /sdcard directory, the USB mode (Settings->Storage->[press menu]->USB computer connection) may matter. Mine was in MTP mode.

o The cable itself might matter:

http : / / www . eileenslounge . com /viewtopic.php?f=42&t=12685

This isn't the cable I used but it was the Motorola cable that came with my Droid 3.

o I read that it might be possible to use fastboot that comes with the Android Toolkit to boot the phone with an image that would put the phone in some sort of maintenance mode with USB debugging enabled. I was considering this as a last resort since I wasn't as familiar with the phone boot menu.

I hope some of this helps someone who might find themselves in a similar position.

-Jeff