DS412+ does not power up :(

[Elextrixman]

Check c290. And U25 not hot

 

[Elextrixman]

CE2(big Cap), u14

 

[Vitaliy]

When I force U31/U32 to open I have +5 on USB board. U14 and Q12 involved in it. U25 (level shifter) getting hot. Where is c290 located? No supply and no short on BIOS. Power is not coming to U23. Looks like REF1 of U25 is connected to supply of U23.

 

[Elextrixman]

Makes me wonder. Are we cross posting to the Shell one, and should be here? LOL!

 

[Vitaliy]

Did not get your question.

 

[Elextrixman]

Do you live in the US?

 

[Elextrixman]

Do you need a parts board? Makes me wonder to just send you a 412 NAS. As the price on these so low these days. Was thinking since if you live here. Send you one free. Or a parts board free.

 

[Telos]

Take a breath before you post on and on without responses. What a mess these threads are.

 

[Elextrixman]

Disaster! LOL!

 

[Elextrixman]

By the way. I just started wearing Pajamas in the Day time. My age. LOL!

 

[Vitaliy]

I'm in Canada. Can you measure R45? Look like it is opened Do you know what Q35 is? Cannot identify it. Do you really have spare parts to share?

 

[Elextrixman]

RJ45 should be open. As its a Balun. Basically a transformer. One side the outside world. The other inside. Send a pic of Q35. As I'm away a bit from my files.

 

[Vitaliy]

R45, not RJ45. It is resistor (?). Transistor marked as NI1Q. Probably fet.

 

[Elextrixman]

R45, not RJ45. It is resistor (?). Transistor marked as NI1Q. Probably fet.

Send a pic of any you want to know?

 

[Elextrixman]

R45, not RJ45. It is resistor (?). Transistor marked as NI1Q. Probably fet.

R is resistor. I see it. Hold a sec

 

[Elextrixman]

10K

 

[Elextrixman]

R45, not RJ45. It is resistor (?). Transistor marked as NI1Q. Probably fet.

Yea. If you want a parts board? Free Just cover ship. I have tons. But that you have to write direct to me.

 

[Vitaliy]

I gave up I'm sure it is small component failed but... Second time I tried to remove 0402 resistor and it got opened. R681. I believe it was 1k.
I just try to trace signal from pin 16 of PIC. I think it should initiate power on. The pin 2 controls blue LED ( I guess).

 

[Elextrixman]

Never give up. LOL! Oddly this is not a easy board to fix. The newer ones are easier. And PIC Chip controls are the same on all boards till today. Except 11 series and earlier. And SLIMs. I call slimes. Do you have a NAS now you can use? Or have a 412 board to compare levels?

 

[Vitaliy]

No, this only one of a kind. I use DNS-320 for years.
Could you check if R486 is installed. I traced signal to this but is is not installed.
Some update:
I traced power button signal to U6 pin75 "Main power switch button input". It has 5V (why 5 if it is related to 3V3B?) It goes low for short time when button is pressed. Main power switch I traced to U6 pin76 "Power supply On-Off output" It has always 1.7v on it. Why 1.7 if it is related to 3V3B. Power button does not change this output. Dead chip? Waiting for conditions? Something with something connected to this output?