Dell G7 7588 notebook cannot be started for repair

Dell G7 7588 notebook cannot be started for repair.

Judge whether it is the standby chip or the voltage is pulled down or leaked, and find the same model as the 5V standby chip PU18V00 chip from the new drawing. The problem is still this 11-pin problem. The resistance of 1 pin connection is 47K, and 1.8V normally appears after replacement.

Machine model: Dell G7588 notebook

Main board number: LA-E993P 1.0

Malfunction: the notebook cannot be turned on.

Maintenance process:

Received a Dell G7588 laptop, the fault description is that it can’t be turned on after one day’s use after changing the screen with high brush frequency of 144hz. Check the appearance that there is no water, and the customer dismantled it and cleaned the dust once.

Disassemble the machine, visually inspect the main board where there is no burning, measure that there is no 5V in standby, only 0.26 in standby 3V, and the resistance value is normal, indicating that the CPU heel bridge is not broken. It is judged that there is a standby chip or a voltage is pulled down or leaked.

Dell G7588 notebook can’t be turned on for maintenance Figure 1

Open the drawing to find the corresponding number PU100 standby chip SY8286. The 11-pin EN 1V only has no voltage. Check the circuit diagram to find out that two resistors and one capacitor are connected in front of EC. After removing the capacitor, there is still no voltage.

It is found that there is no voltage when measuring PR102 to the ground, and there is 1V in PCH and 0V in EC11 pin when measuring PR103. There is no deterioration and corrosion when looking through magnifying glass, and it is replaced by 100K. After retesting, standby 3V has come out and normal 3.3V is found, but 5V is not. Next, repair 5V for standby. Looking for the same model as the chip PU18V00 with 5V standby from the new drawing, the problem is still this 11-pin problem. The resistance of 1 pin connection is 47K, and 1.8V normally appears after replacement.

Dell G7588 notebook can’t be turned on for maintenance Figure 2

After the replacement, 0.09 appears in normal standby, 3V 5V appears in normal standby, and the lighting machine is triggered normally. The hard disk has been removed by the customer and can only enter the BIOS. It only takes 3 seconds to turn on the machine after brushing and restarting twice. After brushing the BIOS, the machine starts. After filling in the relevant information, it automatically restarts and then enters the BIOS. The machine starts normally.

Dell G7588 notebook can’t be turned on for maintenance Figure 3