Dell Laptop Dead.

[IamPritesh]

SO I have a dead dell laptop that does not turn on. I also do not see any shorting when using DC power supply.

The board does have 3 /5 ALways voltage . there is not voltage on PIN 8 of the Bios Chip though.

Also I am attaching a pic and would like to know why I am getting 0 voltage on the other end of the resistor

[IamPritesh]

Re: Dell Laptop Dead.

Anybody please help

[Techtiger]

Re: Dell Laptop Dead.

for me it's normal PQ903 N Channel Mosfet gate Voltage 5V S & D GND
+B 19V with Voltage Dividers 20K &100K 3.64V OK to PQ903 Gate pass to conduct 19V to B+BIAS

send the Schmatic to find out adsent of 3.3V in bios leg 8

[IamPritesh]

Re: Dell Laptop Dead.

Thanks. After giving some heat on the SIO Chip now the laptop starts but has no display and no post.( Schematic attached )
Even after removing the Ram , there is no beep . The fan spins and two LEDS glow. The PCH also slightly warm.

Where should I start now ? Any checkpoints please..

[mcplslg123]

Re: Dell Laptop Dead.

Thanks. After giving some heat on the SIO Chip now the laptop starts but has no display and no post.( Schematic attached )
Even after removing the Ram , there is no beep . The fan spins and two LEDS glow. The PCH also slightly warm.

Where should I start now ? Any checkpoints please..

Check voltages on Vcore coils and Ram. Might be bios issue

[Techtiger]

Re: Dell Laptop Dead.

test all gray coils for voltage
PL700 +VCCGFXCORE
PL701 VCCCORE
PL900+VGA CORE
PL600
PJP300 JUMBER +0.75VS
PJP303 JUMPER +1.5
ect save your old bios and try to flash bios you have 2bios chips i think you have to flash PCH one

[IamPritesh]

Re: Dell Laptop Dead.

PL700 +VCCGFXCORE - No Volts
PL701 VCCCORE - No volts
PL900+VGA CORE - 0.14 Volts

PL600 - 0 volts
PJP300 JUMBER +0.75VS - 0.74 Volts
PJP303 JUMPER +1.5 - 1.48 Volts

[IamPritesh]

Re: Dell Laptop Dead.

Any help friends ?

[Techtiger]

Re: Dell Laptop Dead.

test voltage pin 22 ISL95833 +5VS
PQ700 +B
PQ701 +B
test 5 mosfets for any short

PU600 PIN 12 +VALW


MOST PROB BIOS ISSU TRY TO FLASH BIOS