Hi, couple of days ago had a second Lite5 AC (RouterBOARD SXT 5HacD 2n r2) die with some type of hardware failure.

Both of them died in similar circumstances.

They first start to sporadically connect/disconnect until one day they have difficulty in powering up at all.

Both devices were grounded with drain wire and shielded.

Whats common to both devices (its the same for most of my customers) is that the client is away for several months and the equipment is powered off.

They then come back and once they power up their equipment the Lite5 AC start to deteriorate and die.

Both units were no more than 2 years old and both units had probably been only turned on and used for 10-12 months.

The link to the video below shows what happens when you power on the faulty Lite5 AC.

https://youtu.be/uWpFas7hSXg

What the video does not show, is after several minutes the LED will not come on at all.

But if the device is left for several hours powered down and then powered back up, you will see what is in the video.

Does anybody have any idea what component is going faulty on the mainboards ?

Ive tried changing the power controller RC near the ethernet socket and the diode, but these are not the cause of the issue.

Any guidance would be appreciated.

PS

I dont think this is normal behavior, none of the Lite5 I have (non AC) have this issue and I have been running these for way over 2 years! Also the second one has no signs of oxidization and both units have no sign of any short/burned component etc

These unit looks like it has seen much humidity, how it is mounted?

These unit looks like it has seen much humidity, how it is mounted?

Hi!

Thanks for your response,

Yes, our location has high humidity as we are near the Mediterranean sea.

The Lite5 have/do not show this type of problem.

They are mounted on a steel pole that is attached to the steel cage that holds the water tanks.

Grounded and shielded cat5e cable

So, hopefully the fix I have applied remains,

If this is the case then there would be a high probability that this is either a design issue or a bad SMD component issue.

Basically on the two Lite5 AC I worked on the four small SMD regulators below the main IC (see picture below).



On one of the devices I had to replace all four SMD's while on the other I re-soldered SMD's.

Ive left them on a few hours and they did not return to the 'dead' state, so will see how they hold up over an extended period of time ..........

I will report back when I have more definitive results.

OK so I 'repaired' these devices by removing the four SMDs and soldering a wire from ground to one of the left side pads of one of the the SMDs (lower left).

I cannot find out exactly what these SMDs are to purchase replacements to test.

Can anybody with electronic expertise comment on what job these SMDs have ?

Thanks

PS
I now have five broken units, those that are off for extended periods of time and are then turned on are dying left right and center...........