What does [Failed] really mean in scene test results?

[dex]

 

I'd like to better understand what [Failed] really means in the results of a Scene Test.  I had assumed it indicates a problem device or communication issue with that specific device.  For example, if I see something like this...

----- Scene111 Test Results -----

[Succeeded] Device A
[Succeeded] Device B
[Failed] Device C
[Succeeded] Device D

… then I would assume Device C is having trouble.  A scene test on this scene always produces the same results with that device marked as failed.

However, that same device is in other scenes (with the same peers) and succeeds 100% of the time I run a scene test...  

----- Scene222 Test Results -----
[Succeeded] Device A
[Succeeded] Device B
[Succeeded] Device C
[Succeeded] Device D

----- Scene333 Test Results -----
[Succeeded] Device A
[Succeeded] Device B
[Succeeded] Device C
[Succeeded] Device D

I did a factory reset on Device C (a SwitchLink Dimmer) and did a Restore Device.  Same results. 

I replaced the switch with a brand new one (using ISY's replace device process).  Same results.

I did a Restore Device on every other device in the scene.  Same results.

It may help me troubleshoot if I better understood the possible causes of a device being listed as [Failed] after a scene test.  I suspect this sort of thing has been asked and answered before in this forum, but I was unable to locate anything closely related.  

[Techman]

Run a diagnostics / compare for each device in your scene to see if it shows any damaged / missing links, 

You could also try deleting and recreating the scene. It's possible that something in the scene got corrupted

.

[Brian H]

The Scene Test is a strict communications test.

Turns the Scene being tested On and then Off. It sets the Max Hops=1 and if the module does not ACK with a Hops Left=1.  The test shows a module as failed if the ACK is not received back. Probably if the Hops Left =0.  I suspect that particular module in the tested scene . Is not sending an ACK back with out decreasing  the Hops left count and showing a fail.

I have had a Scene Test show a failed module but in normal use. I have seen no problems with the module.

[Brian H]

If  you are curious.

You could open the Event Viewer in Level 3. Then run the Scene Test and see what is displayed for module in question. In a scene that passed and the scent that the module failed. To see if the Max Hops=1 and what the Max Hops Left= is.

[oberkc]

I recall, too, that a scene test could fail if one of the included devices triggering a program.  If this is a possibility, temporarily disable the program(s) during the scene test.

[dex]

Thank you, all, for the thoughts.  Knowing that the Scene Test restricts to Hops=1 is insightful and, I suspect, part of this issue.  

I do get occasional communication issues on those scenes, so when the Scene Test was very consistently calling out that one device, it becomes a target for deeper troubleshooting.  Since I replaced with a brand new device and see the same test results, that [Failed] result is likely just a symptom of the communication issue, not a smoking gun.

I examined/compared link tables and found no anomalies.  I'll try recreating the scenes and see if I get similar results.  Thanks again for the suggestions.

It would be great if ISY could run a comprehensive system-wide test and spot patterns and enumerate possible problem areas, with links to troubleshooting best practices and processes.  Any such thing exist?

[Techman]

You might also want to make sure that both sides of your powerline are properly bridged using the 4 tap test

https://wiki.universal-devices.com/index.php?title=INSTEON:_Troubleshooting_Communications_Errors