820-2936, Battery Drains Rapidly During Sleep?


I've heard of this issue, but never actually encountered it. Working on an 820-2936 that works fine, but the battery drains as if it's in S0 while it's in sleep/S3/S4. I'm honestly not even sure where to start; maybe one of the power state enables/switches? Customer reports "when I put the unit to sleep each night, even with 50%+ charge, it's dead in the morning and I have to plug the charger in and battery is at 0%".

It just came in today, so I'm testing it now, but is there anything I can look at/for to help narrow down the cause? Would it be something as simple as a bad ISL? The board is very clean, no damage/drops or anything, just this rapid-drain issue. Genuine battery, charger, etc. Issue occurs with multiple different drives and RAM as well (customer purchased duplicates of each thinking that was the issue). Thanks in advance for all help!


Measure if S0 rails go low after putting it to sleep. Check also VCORE while sleeping.

Could also be a software issue so be sure to check with a known good OS you know for sure is sleeping correctly.


Probably had liquid at some point. Check if there is voltage leak through Q3880, check voltage on L3895 when machine is off.