Intermittent WiFi Connection at Startup

[tfjield]

@phaedrux
I do. It had the same problem with the AP in the house, so I thought maybe it needed a higher signal strength, so I put a new AP close to it. (The strength was good already, but I didn't want to be blasting everything else indoors if it needed more.) But I can crank up the indoor power temporarily and try connecting to that one again (different SSID's, so that's easy) to see if it makes a difference.

I can't do this until Monday, though. I'm sitting in a plane just about to take off! ️

[oliof]

@tfjield is that still another Unifi AP, or some other make/model?

[tfjield]

@oliof It's Unifi. The current is model UAP, and the other one I can test is U6-LR.

[tfjield]

@oliof @Phaedrux
I may have found something. On a hunch, I decided to replace the SD card with a faster one, thinking that there might be some kind of race condition occurring during startup.

The card that came with it is a SanDisk Edge 8 GB class 4. Here's a stock image of the card:

I replaced it with a SanDisk Ultra.

With the original card it would boot and connect to WiFi no more than half the time. After replacing the card, it's connected 5 out of 5 reboots. I'll continue testing, but it seems much better!

EDIT: This is on the same AP; I've only changed the card.

[Exerqtor]

@tfjield Interesting, keep us updated on this please 😅

[tfjield]

@exerqtor
With the new card I've rebooted about 18 times so far, and it's only failed twice. Looks like a significant improvement, but not 100%.

To be completely sure it's not something else, I'll swap the old card back in later and see what happens.

[tfjield]

Well, it turns out that this was not the fix. As time went on, the number of times it would fail vs. the number of times that it would succeed has increased a lot. We're back to 50/50 or greater failure rate.

To this day, once the WiFi is connected I have never lost connection.

I suppose this could be a hardware problem, but it sure seems more like some kind of race condition. Is there anything I can do to help determine the root cause for the failure?

[Phaedrux]

Can you snag a close up pic of the soldering on the wifi module?

[tfjield]

@phaedrux
These aren't great... Is there something specific you're looking for? If so, I can try to highlight it better. And these were with a cell phone camera... If these aren't good enough, I can pull out the USB microscope.

[Phaedrux]

Thanks for the photos. I will pass them on for evaluation.

[Phaedrux]

I don't suppose you could get some better photos? Might have to take the board out.

[tfjield]

@phaedrux Sure, I can get better photos. Anything in particular I should try to capture? Are you looking for a cold solder joint? Perhaps it would be better if I viewed it from a 45° angle...

[tfjield]

@phaedrux Here are some better pictures. I tried to image near the pads on the bottom.

That's about the best I can do.

[Phaedrux]

Thanks I'll pass those along.

[dc42]

@tfjield thanks for the photos.

I think the soldering is OK. The WiFi modules have gold plated recesses on the sides - see photo below. The solder appears to have wicked up int those recesses, so it should be making good contact.

[Exerqtor]

@dc42

Haven't restarted my machine in a while, but i had to now due to some maintenance. And when i try to turn it back on it's doing this crap again

I'm on my 16th power toggle now without it connecting / starting the wifi module or what the F's actually going on.

It must be something fishy on the FW side causing this since it's happening on/off like it is, were it an HW issue the fault should persist shouldn't it?

EDIT:
To be clear since i forgot to mention it, i'm running all the latest FW (3.4.4).

[Phaedrux]

@Exerqtor What do the solder points on the edges of the wifi module look like on your board?

If you use a PanelDue or USB terminal, can you send the M552 S1 commands to enable the module and see if it reports any errors?

[Exerqtor]

@Phaedrux said in Intermittent WiFi Connection at Startup:

@Exerqtor What do the solder points on the edges of the wifi module look like on your board?

Pretty much a carbon copy of tfjield's ones. So i don't think it's a HW issue tbh.

If you use a PanelDue or USB terminal, can you send the M552 S1 commands to enable the module and see if it reports any errors?

Yeah i've got a due, but nothing happen if i just input M552 S1. This is the error i get if i restart the module or machine at least:

EDIT;
Have you found a solution or work-arround for this @tfjield? Or have you just also had the machine in a steady on-state the last 4 months? 😅

[Phaedrux]

@Exerqtor How old is your board? Do you feel comfortable giving the solder points a touch with an iron and a dab of fresh solder?

[Exerqtor]

@Phaedrux said in Intermittent WiFi Connection at Startup:

@Exerqtor How old is your board? Do you feel comfortable giving the solder points a touch with an iron and a dab of fresh solder?

Uhm i'm not 100% sute to be honest!
But yeah i'll pull out the iron and some flux paste and give it a reflow tomorrow and see if it does anything ✌️