Lenovo T430 Notebook Won’t Turn On repaired

Lenovo T430 Notebook Won’t Turn On repaired

Machine model: Lenovo T430

Malfunction: Notebook Won’t Turn On

Maintenance process: there is no standby for taking over this board, and there is no VCC Diode value is normal in the public point. All Inductor diode value on the test board are normal, so Xinzhizao Soft is turned on.

Lenovo T430 Notebook Won’t Turn On repaired Figure 1.

Measuring the 19V of Q9 G level of P-channel isolation tube is abnormal, and then measuring the -PWRSHUTDOWN of G level to low level, that’s the problem.

Lenovo T430 Notebook Won’t Turn On repaired Figure 2.

Transfer to U101 which generates -PWRSHUTDOWN, and test VREGIN20 is normal, vcc3sw3.3v, bat _ volt7.2v and th _ dtct0v are all normal. There is no problem with Current protection in the public spot VCC. Just pry U101 96PIN -PWRSHUTDOWN.

Lenovo T430 Notebook Won’t Turn On repaired Figure 3.

Test again that -PWRSHUTDOWN is still at low level, which has nothing to do with U101. Just check the line of -PWRSHUTDOWN.

Lenovo T430 Notebook Won’t Turn On repaired Figure 4.
-PWRSHUTDOWN is high when I move C228.

Lenovo T430 Notebook Won’t Turn On repaired Figure 5.

Lenovo T430 Notebook Won’t Turn On repaired Figure 6.

Solder U101 96PIN back, send a booting up drawing, and the maintenance is over.

Lenovo T430 Notebook Won’t Turn On repaired Figure 7.