Black screen cant get watch face to turn back, everything else still functions (Heart Rate, Sleep Tracking, ect..)

I'am Having the same problem here, after a year using my 165 Music.

I'am having the exactly the same problem here with my 165 music, after a year using it. 

Sometimes the display just turn black, but the watch still function and i can hear the beeps.

Same problem here. Watch is alive but the screen is black. The reboot doesn't fix it.

This just happened to me today, too. Initially, a reset (can't remember which kind) through the Garmin Connect app on my phone brought the screen back to life. I reconnected to the phone and reloaded a backup. 20 minutes later, I went to start a run, the screen was black again, and again would not wake up. Chatted with customer support for an hour. The tech kept answering, "interesting," and told me to upload a video demonstrating how the watch screen remained black even as the sensors flashed green and it synced with Garmin Express.He eventually offered to replace the watch. Inconvenient and annoying, considering this is the second Garmin model I've had to return for hardware issues, but hopefully I'll be tracking my training again in a week.

Exactly whats happening to me now the customer support is of no help

I have also just started having this issue. It's been a while since I've bought the device (> 6 months). I've found that it keeps running, and you use the device as if everything were normal except the screen doesn't work/turn on at all. I can get to my stopwatch with muscle memory, all the vibrations are correct. I can hard restart the device, but the screen still doesn't work when doing that; I can tell that the device restarts because it behaves exactly like it would when I do the same with the screen on; heart rate sensor shuts off even when it's on my skin, button presses after restart cause the specific vibrations I expect, etc. It is almost like the display has become disconnected from the rest of the watch. The first time (two days ago) the screen didn't come back on until anywhere between 5 and 10 hours later.

Garmin absolutely needs to address this, because if the bug/design flaw doesn't get fixed, I can't ever recommend people depend on Garmin for whatever hike/run they're doing; they might get lost and can't use their watch to get back. In fact, I would actually actively steer them away from the company at this point simply because a device power off + power on can't fix this right when it's happening.

I recommend you chat with customer support. My experience was somewhat annoying, going through troubleshooting with them for an hour, having to send them video of the watch not working properly, but ultimately they offered to replace the watch. I mentioned to the rep that I had seen several examples on this forum of this issue, and they said they were not aware of it.

Just want to follow up on this thread. Contacted support tried all of the various resets ect… I have now had to replace this same watch 2 times now, no explanation to what the issue is, how to prevent it from happening, or anything really. While I am glad they keep offering to send me a new device it’s really inconvenient for training especially when you’re mid block and you have no watch to track your data. All in all I have not found anything to fix the issue once it occurs other than to contact support and get the device replaced. 

Exact same issue today with the REPLACEMENT Forerunner 165 which arrived YESTERDAY only!! My previous Forerunner had a pressure sensor failure after 18 months and it couldn't count flights of stairs. This replacement is already suffering the same 'Black Screen of Death' as everyone else here. Beeping, making sounds, tracking it seems, but Black Display. Was unable to do a run today. Came back to life randomly.