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[help] FIRST POST: 820-00840 DEAD AND HOT AS HELL
- Thread starter phantom
- Start date
U3900 is the camera controller.
Do you get correct voltage on its coils?
Do you get correct voltage on its coils?
L3901/2?
Did you also check the traces of BootROM resistors?
Tried the BIOS?
This board can boot without U3900.
ALL_SYS_PWRGD stays high?
Check U7100 voltages; pins 41, 42, 48.
Tried the BIOS?
This board can boot without U3900.
ALL_SYS_PWRGD stays high?
Check U7100 voltages; pins 41, 42, 48.
Keep U3900 out, if you have doubts; is not needed to boot.
"pin 42 0v"
Check diode mode to ground there.
If short, bad C7102, or U7100.
Anyway, R7192 is burnt/open.
Check diode mode to ground there.
If short, bad C7102, or U7100.
Anyway, R7192 is burnt/open.
Replace again R7192; it got burnt because of bad U7100.
I never said to replace R7192 BEFORE finding the cause of short.
I never said to replace R7192 BEFORE finding the cause of short.
Do you have 5V at pin1/R7192?
If yes, same voltage must be found on pin2; is just 1 ohm resistor (if not burnt).
If yes, same voltage must be found on pin2; is just 1 ohm resistor (if not burnt).
Do you get now L7210/20 voltage?
It should drop to aprox 0.65V after 10-15s; check that.
Also check for USB activity.
If not, try known good BIOS, clean ME.
drive.google.com
Also check for USB activity.
If not, try known good BIOS, clean ME.
820-00840 8HV22 Medusa clean ME + PRAM.bin
drive.google.com