Hello, I have a problem with a Lenovo G50-30, motherboard LA-B102P Rev: 1.0, ZIWBO/B1/E0, 2014-06-12
Motherboard powers on (power LED is OK), but no POST, no video (internal or external), no beep, no Caps lock LED indication, nothing.
It is not a "no backlight" scenario - there is nothing on the screen.
Pressing the power button for several seconds turns the motherboard off. So at least that logic is working.
I tried known good compatible DDR3L RAM
All power rails seem to be OK:
PL_coil = stand_by voltage, power_on voltage
===========================
PL301 = 20.4V, 20.4V
PL302 = 2.74V, 2.74V (without battery)
PL402 = 3.38V, 3.38V
- PG signal PU401,pin2 = 2.8V
PL404 = 5.1V, 5.1V
- PG signal PU402,pin2 = 0.2V
PL502 = 0V, 1.37V
- PG signal PU501,pin10 = 1.37V when power_on
PL601 = 1.8V, 1.8V
- PG signal PU601,pin5 = 0.57V
PL603 = 0V, 1V
- PG signal PU602,pin2 = 3.3V
PL701 = 0V, 1.06V
- PG signal PU701,pin5 = 0.67V when power_on
PL902 = 0V, 0.9V
PL903 = 0V, 0.78V
- PG signal PU901
- pin8 = 5V
- pin15 = 3.3V when power_on
- pin22 = 5V
- pin27 = 3.3V when power_on
Voltages on:
EEPROM 1st pin = 1.8V
ETC battery = 3V
DRAMRST# = 1.34V
PLTRST# = 1.8V
Measurements of other KBC pins (ENE KB9012QF A4) attached in the table, see picture.
Not measured:
PL101, PL102, PL201, PL202, PL401, PL403, PL501, PL602, PL901
Motherboard powers on (power LED is OK), but no POST, no video (internal or external), no beep, no Caps lock LED indication, nothing.
It is not a "no backlight" scenario - there is nothing on the screen.
Pressing the power button for several seconds turns the motherboard off. So at least that logic is working.
I tried known good compatible DDR3L RAM
All power rails seem to be OK:
PL_coil = stand_by voltage, power_on voltage
===========================
PL301 = 20.4V, 20.4V
PL302 = 2.74V, 2.74V (without battery)
PL402 = 3.38V, 3.38V
- PG signal PU401,pin2 = 2.8V
PL404 = 5.1V, 5.1V
- PG signal PU402,pin2 = 0.2V
PL502 = 0V, 1.37V
- PG signal PU501,pin10 = 1.37V when power_on
PL601 = 1.8V, 1.8V
- PG signal PU601,pin5 = 0.57V
PL603 = 0V, 1V
- PG signal PU602,pin2 = 3.3V
PL701 = 0V, 1.06V
- PG signal PU701,pin5 = 0.67V when power_on
PL902 = 0V, 0.9V
PL903 = 0V, 0.78V
- PG signal PU901
- pin8 = 5V
- pin15 = 3.3V when power_on
- pin22 = 5V
- pin27 = 3.3V when power_on
Voltages on:
EEPROM 1st pin = 1.8V
ETC battery = 3V
DRAMRST# = 1.34V
PLTRST# = 1.8V
Measurements of other KBC pins (ENE KB9012QF A4) attached in the table, see picture.
Not measured:
PL101, PL102, PL201, PL202, PL401, PL403, PL501, PL602, PL901
Comment