Boot sequence 0.009 A only
Fuses are OK
NO UART…but 3.3v on RX and TX
No short around SB
Standby voltage seems ok
@Calvin help!
Missing standby 5V on Dialog!
Where it is generated?
The 5V_EVER line is powered by the left mosfet. Left side 12V input and right side 5V output.
Downstream are the F7001, F7002 and F7003 fuses.
Everything’s fine here, 5V is coming.
I’m thinking maybe the BIOS is corrupted, but is there a connection with Dialog without 5V?
Sorry, I don’t get it. The 5V line is the input for the SB pmic DA9065.
Sorry, I have a DA9081.
I referenced this and the 5V input is there properly.
I can’t find a short around the SB.
Boot Seq. 0.009 and no UART
Ok. The DA9081/RT5127 is the pmic for the SSD. It is only active if system is started.
But the input 5V_EVER should be present. If not please check the fuse F7502 for continuity. And if blown check the caps on the backside of the DA9081 for shorts. I had some cases where one of the caps was shorted.
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Update:
DA9081/RT5127 standby voltages OK (5V)
All fuses OK
Reflashed BIOS in same IC
Nothing!
Stuck on 0.009 and no UART.
Bad SB?
But I found no shorts under it and apparently nowhere else!
It could be bad IC bios but I don’t think so, it is read normally by ch341a
There are many ways a chip can fail. A short is a nice indicator to find, but not every failure of a chip is a short. My PS5 today was a bad SSD controller without any shorts or funny readings.
If all power rails for the SB are present and not even UART is active, I would change the SB.
Did you clean underneath the southbridge if there is any leftover flux?
Update:
I replaced the sound bridge, unfortunately the same situation. 3.3 volts are present on TX and RX but the UART doesn’t read at all.
I replaced the bios chip by reprogramming it, nothing happened.
sound bridge 
Damn voice dictation
@Calvin I got more information. The fan caused a short circuit. PWN / GND . Now I get OL on pwn pin. SB Changed but maybe it was bad I’ll try again soon
With the new SB still oL at the fan PWM pin?
yes, But I have to check if the SB is bad. Bought on Ali already reballed.
No, the connector is intact. I found the SB PWM pad you mentioned slightly damaged. I fixed it, put in a new SB, and now it’s working again.
There’s a strange anomaly, though. Sometimes it doesn’t start, sometimes it starts but with a solid blue LED (the fan is running).
What could it be?
Still no UART output?
Yes, it works fine now, but no errors. The log is clean. Crystal oscillator? I’ve never seen a solid blue LED.
Boot sequence normal, but remains at 0.015 sleep