Hi, i’m from Brazil, and I fix Rb’s(I try).
I have some PDF with repair instructions.
We could trade ideias for RB’s with NON WARRANTY.
A picture with the faulty components that i’ve seen.
The blue components are changed to do the RB turn on.
The Red components are changed to me connect to Ethers.
The green components are changed to do the board boot.
->In the CPU just was made reflowed.
Hello Rafaela.
Nice idea to discuss.
I also (try to) repair RBs.
For the Ethernet connectors part. I haven’t ever changed them (if they weren’t mecanically damaged of course). Except the Ether1, that has the PoE pins, i don’t see how the others can affect the turning on of the RB.
Also. I wanted to ask. How do you test and measure the components in blue??
The Ether ports, I tested but don’t find nothing of different. So I knew that C826(3,3V) was short circuited with GND. I removed component by component and tested if fade the short. If you will try to repair a board that don’t turn on, I advise change first the J603.
In the other cases, I check the voltage of the pin 7 of U803 and isn’t 3,3V(like another that I was comparing).
The D801 and the Q801 I found easily the datasheet, and tested.
And the L801 was with a resistence diferent than 0 Ohms.
More any question? 
you can try to ask your distributor for available repair manuals.
I have this manuals. But have other problens.
I would like of know, what happen, and where is the defect, of the board that turn on, connect by the ether, and don’t appear nothing in winbox.
there can be number of problems - starting from hardware problems with damaged port controllers ending with damaged RouterOS installation that can be bought back with simple netinstall.
Could you help me to find at least one hardware problem? -
Here you have a repair manual
http://www.routerboard.sk/files/troubleshooting.zip
I have this manuals, and others. But have some problems that have another solution.
Sometimes I tested until the ‘The board is unrepairable’ and after I find the solution.
I wanna know about the hardware problens that are out of this repair manual.
Any ideia for when the RB is on, and after a time the RB shutdown? And don’t turn on more?
Yeah Rafaela. You are right. There are plenty of problems i run into that are not covered on the repair manuals of the distributors.
The question you are asking (about nothing showing in winbox) has happened to me many times with the new version of the RB411. I solved it by changing the ether chip. Even if it connects (green led on ether connector turns on), it doesn’t really work.
Mostly of the times is a damaged ether chip that looses packets in rx, tx or both ways.
The simplest test i do about the state of the ether chip is trying to boot the routerboard via ethernet with netinstall. If it doesn’t connect, even if the led is lit, i proceed on changing the ethernet chip..
After repairing i test with speedtest of MT and see if there is any packet loss.
Do you know a better way??
No… in the mostly of times, the buzzer(B1) of the board don’t honk. So I can’t boot the RB via ether with netinstall. 
Do you have any ideia? -
No boot is often a power problem. Check chemical capacitors. 90 % of problems do come from them.
Dissolder and check the value. 1/2 original value is generaly ok. 1/5 or 1/10 is not ok…
In my city I don’t find any capacimeter. So I’m buying by a store in anothe city.
When the capacimeter arrive, I’ll test and post here.
More any help?
If you want more help, you need to remove the bra :=)
xDDDD
man..
Generally bad capacitors have a curved top, or they can even explode. This is why there are small breaking marks on the top, to avoid too powerful explosions.
If electronic circuits didn’t had chemical capacitors, they would be at least ten times more reliable in the long term.
Remove the Bra of Brazilian?
rsrs
sorry, but why?
Fiptec, I can show you my nipples if you want to… xD
Ow.. now I understand, bra (sutiã in portuguese), rsrs.
If someone help, who knows.
rsrsrsrs