wifi sync not working

So i did a test with my router since i was getting the same issue with WIFI sync. Both 2.4 and 5g were combined and I'm using a WIFI 6 router (AX).

Once i split the WIFI networks separately (2.4 and 5g), Wifi sync worked right away on the 1040.

Sometimes Garmin is not always to blame.. Yes Wifi 6 is a new standard... but on the other hand, it does not need wifi6 bandwidth to transfer a course.. which lowers the cost of the edge device for garmin.. just sayin... 

Using Firmware 19.22

I too had issues with the Wi-Fi connect gremlin. But a firmware update seemed to fix issue. One thing that you must make sure of is that your SSID`s for your 2.4ghz and 5ghz bands are not the same. This not only causes issues with Garmin, but other devices have problems with the same SSID. Another issue is the control channel you use for the 2.4ghz network. I always select a manual channel. If you live in a crowded community, this is a big issue. You must select your control channel to a channel that has very little use and one that is not one of your neighbors. Control channel crowding causes all sorts of hate and discontent on a 2.4ghz wireless network. Lastly, unhide that SSID. I know the net says it's for security purposes, but that about as true as trump won the election. Yes, it`s one thing that a hacker doesn`t have access too, but if someone's going to hack your wireless network, they don`t need to see the SSID to hack your domain. Oh, I forgot to also mention virus checkers. Make sure that you have a rule set to allow your virus checker access to Garmin device addresses. I do think there may be some more room for improvement on Garmins` side, but make sure you're not causing problems on your end.

This actually works. Would be nice if Garmin acknowledged that it's clearly a bug, when a reset will fix it, instead of having users mess around with their wifi settings.

I did exactly what you said.. newest firmware.. 20.19..  separate SSID 2.4 GHz network, I can’t choose channels in my Deco M9 configuration…. 
this network works for fenix7, index scale… but on 1040 I’m getting always “Sync Failed”….

I still think, sorting out WiFi… is the easiest thing in the world.. having this tech for so long… It is ridiculous to have issues like this. 

I also get "Sync Fail" with every 20.19 Wi-Fi sync activation BUT the odd thing is that it actually works every time both up (sync rides to GC) and down (GPS files, new software versions and "Send to Device" courses). And the even odder thing is that I ONLY get Sync Fail with Production Software releases. I participate in the beta program and if I have a beta version I get "Sync Success" EVERY TIME but as soon as I install the production version I get the "Sync Fail" every time, same wi-fi network, sitting at the same place in front of the wi-Fi modem.

And the oddest thing is that this beta/production has happened with every version for the last 3 versions at least 18.x (5 beta versions then production), 19.x (6 betas/production), 20.x (11 betas then production)

Happy if someone can explain this but it surely must give Garmin a clue as to what is doing this, what is different between betas and production versions to give the different status messages but in the end always works? Garmin has had an upload of my device files 3 times chasing other issues in the betas and has never found issues with the syncing, I suppose because it is working during the betas.

Man haha glad that you wrote this…

I just did a test, disabled Bluetooth ok my phone and started a fake ride… stopped and it synced via WiFi… LOL

yes the message still shows Sync Failed… like you said. Well I didn’t try it on beta, for quite some time, since 20.19 came out, it triggered me to do some tests.

so.. it works, it’s just the message that is wrong on non-beta software.. 

I'm also seeing this issue on Edge 840 (firmware 20.19), I'm posting here because this thread already got traction and I believe it's the same issue.

I have router set exactly as mentioned earlier, separate 2.4 network etc. Ever time I run "wifi sync" I'm getting an error "Sync failed". There are 2 clues hinting that it's not a problem of my router configuration:

1. I made this screenshot on my router's traffic monitor. This is what traffic looks like during a failed sync. Garmin Edge is the only device with access to this network, so it manages to download 24.7KB and upload 46.1KB before failing.

2. If I completely turn off the device, power it back on and then very quickly go to menu -> Connected Features -> Wi-Fi I can see that sync is already in state "Transfer in progress" (probably triggered during startup sequence) and then, miraculously, changes to "sync complete". So it's the only way for me to get a successful sync, triggering it by restarting the device.

Feel free to contact me if you have further questions or you need assistance debugging it.

Another thing that can cause issues with a router is virus protector if it has one. Another item which is an issue is with certificates. Make sure your router is setup so it can process the link. Not sure what brand of router you have, but make sure you still have the router credentials still setup in the Garmin device. My 1040 somehow had its link credentials get messed up in the 1040 and went through the same bs. Had to delete link and restart from scratch with finding router and then re-entering passcode to get things going. Feel your pain. 

I did more testing. I turned off bluetooth on my phone (and bluetooth stayed off whole time) and did following steps:

1. Turned off Garmin Edge unit

2. Went to trainerroad and marked incoming workout as outside workout

3. Turned on garmin edge, workout appeared on Home Screen, so pulling workout using wifi worked

4. Finished the workout, after saving the activity it was immediately pushed to Garmin Connect and trainerroad, so pushing activity using wifi also worked.

5. Still having bluetooth off I went to Garmin connect and created new course. Then on Garmin edge I went to connected features -> wifi -> sync now. Message said "sync failed" again but when I went to Home Screen I saw new course there. So pulling courses using wifi works as well.

I'm not sure what doesn't work. Is it just wrong message after pressing sync now? One thing is certain, message "Sync failed" is too ambiguous and it's impossible to know what's really going on. I don't really know which part of sync is failing, seems like it's not pulling workouts and courses, and not pushing activities.

Yep "sync fail" is a failure of message not syncing

https://forums.garmin.com/sports-fitness/cycling/f/edge-1040-series/335738/wifi-sync-not-working/1755532#1755532