06-01-2019 08:39 PM
I went to start my laptop, hit the power button and the fans came on for about 2 seconds then went off. then after another second, the fan would spool up then shut off, the machine will keep doing this until I disconnect AC charger. The weird part is, when the charger is disconnected, the laptop will boot up and operate normally. If I plug in the AC power, the battery charging light comes on. As soon as I hit the power button with the charger connected, it starts the fan on and off routine.
I am afraid I need a new motherboard unless someone else has had this problem before and knows a fix?
It sounds to me like a voltage regulator issue or some kind of voltage problem.
06-04-2019 04:57 AM
Welcome to the community forums.
Have you tried using a different charger? Does the laptop charging fine while it is off? Try updating the BIOS. You may download the updated BIOS for P400 here: https://support.lenovo.com/us/en/. Once done, try uninstalling/reinstalling the ACPI and battery driver in device manager. Open device manager, locate battery and expand. You should see the word ACPI (Advanced Configuration and Power Interface) and battery. Right click the driver and choose uninstall. Restart the computer to automatically reinstall the default driver of the battery. Update us how it goes.
06-04-2019 07:49 PM - edited 06-04-2019 07:50 PM
I tried a different charger and got the same results. The battery charging light comes on when the charger is plugged in, so I let it charge overnight. Now the laptop will not even come on with power disconnected. Still, when I plug the charger in and hit power button, the fans come on and the power light comes on for about 2 seconds, the light goes off and fans stop for about 2 seconds then it cycles through the same thing over and over until I either hold down the power button or disconnect charger. It did the exact same thing with a brand new charger too.
So this means I cannot update bios as the laptop will not power on long enough to do that. Also, nothing comes on the screen at all when it is going off and on.
06-05-2019 06:56 AM
Looks like a hardware issue. Is your laptop still under warranty? If yes, then we suggest contacting our local support here: https://pcsupport.lenovo.com/us/en/supportphonelist to set up a repair request. If the laptop is out of warranty, you may visit a third party local service center for repair options.