Lenovo ideapad 100 - it switches off almost immediately

[davideok]

Hi all,
Please help me with my PC that doesn't work anymore – a Lenovo Ideapad 100 ibd15
If I press the power on button the led turns on but in less than a second it switches off.
I run the below tests, would you suggest me the next ones?

Power supply seems ok- Charging led is on if I plug the power supply cable, 20V on the power supply plug
I disassembled PC
20V on the on the MB (pins soldered on the MB)
I disconnected the battery (it is connected to the MB via cable)
• Power on button pressed for 20sec
• Switch on test without battery failed (led on and almost immediately switched off)
CD driver disconnected - same issue
keyboard cable disconnected - with and without battery test failed (same issue)
trackpad cable disconnected - with and without battery test failed
MB battery disconnected (w/o battery and power cable) and waited 20min – test failed
HD, wireless card disconnected - test failed
Display disconnected - test failed

would you suggest me the next ones? Than you in advance
have a nice day
Davideok

[rammstein9910]

Re: Lenovo ideapad 100 - it switches off almost immediately

I'm guessing I have the same problem with this type of laptop.

[emestee]

Re: Lenovo ideapad 100 - it switches off almost immediately

Sounds like the charger kicks into protection mode. Check the resistance of the main power rail first, then the first two mosfets that control it, the one that switches the battery and the two that generate charging voltage.