I’ve had exactly the same issue with x3 IKEA E1743 switches that have all been showing ‘Update available’ in HA for months and months, and they always fail! Here’s what I have done today to get them to update:
- Open up the Z2M interface in HA
- Hit ‘OTA’ from the top menu, and identify which switch you want to update
- Click ‘Update device firmware’. A confirmation dialogue will appear, but DON’T YET hit the confirmation button to start the update
- On your physical IKEA switch, press the ON or OFF button
- Quickly press the confirmation button in Z2M to begin the update. You should see a small notification in Z2M indicating the update has begun
- Every ~1 second, alternate pressing the ON then OFF button on your physical IKEA switch to keep ‘awake’ and stop it going to sleep
- Stop pressing the buttons once you see a notification along the lines of ‘Update of X switch at 0% complete, X mins remaining’ (this usually takes 5-10 secs or so)
It seems that these switches go to sleep very quickly, so following these steps means that when the update begins, the switch doesn’t go to sleep and cause it to fail. Once the update has started, the switch seems to stay awake.
I did read somewhere that Z2M doesn’t handle updating multiple switches at the same time very well, so I’m doing my x3 sequentially - but it might work doing them at the same time!
The updates take some time - the first one I did took ~100 minutes, but it did complete successfully. Currently doing the second one…