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820-3437-b green light no power
- Thread starter Sr. Robot
- Start date
Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L, at same time.
If present. check for pulse at PM_SLP_S4/3_L.
Be aware, this board should restart 2 times before booting, when charger is connected.
If present. check for pulse at PM_SLP_S4/3_L.
Be aware, this board should restart 2 times before booting, when charger is connected.
Then check if each bg coil pulse at same time.
Also check pins 7 & 3 of U1950.
Also check pins 7 & 3 of U1950.
Check for pulse at pins 5 & 6 of U1950.
Then pin 3 MUST pulse too.
If not, change U1950.
If not, change U1950.
Power cycles every 5 seconds, or just 1, or 2 pulses when connect charger?
Try starting in SMC bypass.
Try starting in SMC bypass.
Can you catch any pulse at PLT_RESET_L?
Check all SPI Bus Series Termination resistors and their traces.
Clean/remove J6100, if needed.
Try known good working BIOS.
Clean/remove J6100, if needed.
Try known good working BIOS.
R6115 was giving me 380 ohms where it should be 15. I replaced it for a 15 one.
There was a trace missing from R6128 to R6123 and i soldered a wire, it has continuity now.
I clenaed J6100 and it looks pretty, should i still replace it?
U6100 is recognized by the programmer. I reprogrammed the BIOS with one from another 820-3437.
Still not turning on.
I noticed wheni try to turn on SMC bypass the fan spins for a sec then stops, then again and again.
There was a trace missing from R6128 to R6123 and i soldered a wire, it has continuity now.
I clenaed J6100 and it looks pretty, should i still replace it?
U6100 is recognized by the programmer. I reprogrammed the BIOS with one from another 820-3437.
Still not turning on.
I noticed wheni try to turn on SMC bypass the fan spins for a sec then stops, then again and again.
You can remove J6100, if do not use it to flash U6100.
We have tested 3437 BIOS files posted on the forum for sure.
drive.google.com
Just in case...
We have tested 3437 BIOS files posted on the forum for sure.
820-3437-Working-CleanME.rar
drive.google.com