IdeaPad gaming 3 15Imh05

[marcelofct]

Hello, I have the following problem, when connecting the original charger or connected to a power source, the laptop consumes 20v and 0.140mah, the backlight keyboard turns on and off. power light is the same
I have 3v and 5v always stable, check for liquid spills and it looks in perfect condition.
reviewing I arrived at IC TI2296 attached image
that at the +3VS output it drops but it is not shorted, I changed it and it remains the same, that's why I need your help to solve it
If you have any help, please stay tuned.

thank you!!

[marcelofct]

Re: IdeaPad gaming 3 15Imh05

Help !!

[reformatt]

Re: IdeaPad gaming 3 15Imh05

Motherboard number and link to schematic is a good start. I assume it's a LA-J561P from a quick search on the forum.

Assume you have tried all the basics, like CMOS reset, disconnect all ribbon cables from the motherboard, check power supply is the one rated for the laptop etc. If that is clear, then that behaviour is indicative of a missing power rail during the power sequence. That is on the schematic on pg 5.

First thing I do is run around each coil with a meter seeing if any rail is shorted. Then check each coil voltage during power on to see which comes up and which doesn't using the power sequence. Given it's a gaming system, I usually check the CPU MOSFET's first as these are often shorted.