Technical Support LENOVO 330-15IKB NM-B451 TURNS OFF SUDDENLY ON BATTERY

[Ipart]

The laptop starts up, the battery charges properly. When disconnect ac adapter even though the battery is 100%, the laptop turns off suddenly after a while. When turned on on the battery itself, it starts and turns off after a while. With the new battery it is identical. All mosfets look good. I replaced the bq charger, without any changes. How can I find out what is causing the problem.

 

[Ahmad Safari]

Hello
The battery connector has several pins that you need to measure and tell me the voltage.
1- Voltage + battery
2- Data pin voltage
3-Clock pin voltage
4- Battery detect voltage, which decreases from 3 volts to 0 volts when the battery is inserted.
Measure the voltage of these pins with and without battery and tell me the values.

Note: The data and clock path usually pass through resistors that sometimes burn and their resistance increases, for example, it is 330 ohms, it is about 1 kilo ohms...
Check them out too.

 

[Ipart]

Hello
The battery connector has several pins that you need to measure and tell me the voltage.
1- Voltage + battery
2- Data pin voltage
3-Clock pin voltage
4- Battery detect voltage, which decreases from 3 volts to 0 volts when the battery is inserted.
Measure the voltage of these pins with and without battery and tell me the values.

Note: The data and clock path usually pass through resistors that sometimes burn and their resistance increases, for example, it is 330 ohms, it is about 1 kilo ohms...
Check them out too.

Without battery
1- Voltage + battery 8,4V
2- Data pin voltage 3,3V 30kOhm to GND
3-Clock pin voltage 3,3V 30kOhm to GND
4- Battery detect voltage 3,3V 100kOhm to GND
With battery
1- Voltage + battery 8,4V
2- Data pin voltage 3,3V
3-Clock pin voltage 3,3V
4- Battery detect voltage 0,3V