Question Lenovo Ideapad S145-15IIL: Power Cycling Issue

[Estebanshoo]

My laptop has been behaving erratically when I try to power it on. The power light stays on for about 20 seconds (I can hear the fan start up), but then everything shuts off, and the cycle repeats. This only happens when the laptop is plugged into the power outlet. Without the power cable, the laptop powers on for about 20 seconds, then shuts off, but the cycle does not repeat. However, when I connect the charger, the laptop turns on automatically, without pressing the power button.

What I’ve tried:

• Hard reset: Pressed and held the power button for 20-30 seconds.
• No peripherals: The laptop has no peripherals connected.
• Memory: I’ve tested with just one memory stick (the only one installed), and the laptop does not start without it.
• BIOS: I’ve updated the BIOS and restored factory settings.
• No charger: Tried booting without the charger; still turns off after 20 seconds, but no repeating cycle.

Despite these steps, the issue persists, and sometimes, with no clear pattern, the laptop manages to start normally. I’m trying to understand what variable might be causing this inconsistent behavior under seemingly identical conditions.

Any advice or suggestions would be greatly appreciated. I’m trying to avoid a complete motherboard replacement if possible.

 

[Dave8671]

Hi
Can you tell if the battery is it charging when the power supply is connected? I think the first step is getting the power charger tested. Most computer repair shops can test it.

 

[Estebanshoo]

Hi Dave, thank you so much for your response...the one and only hehe. Yes, battery is charging normaly, in fact I already tested 3 batteries and everything ok when they charge. I even tried a new charger and it happens the same. Some part maybe is loose becasue the other day i moved the laptop and the screen goes to lalaland....