BCConnection
Member
This is my experience on this repair. Not sure of the root cause but this got it going without replacing major parts of the system.
Issue: On boot up the Macbook has Trackpad and Keyboard function but if you close the lid it loses Trackpad and Keyboard function.
When the Mac is put into sleep mode with lid open Trackpad and Keyboard still work its only when the lid was closed they would lose function.
Reason for this function loss, IPD_PWR_EN from PMU (PMIC) 1.8v line dropping to 0v
This normally shuts on and off based on lid position but it seems to go low and stick low 0v on lid close.
This may be resolved with replacing the PMU but it may also be something beyond the PMU.
I found the easiest solution was to snag a 1v8 line from a secondary source to power these rails. I used 3v3_S2_EN line which is high all the time when lid is closed. This will cause I assume some power usage while the lid is closed (assuming minimal) but it solves the issue with the low IPD_PWR_EN being lost after lid close.
Issue: On boot up the Macbook has Trackpad and Keyboard function but if you close the lid it loses Trackpad and Keyboard function.
When the Mac is put into sleep mode with lid open Trackpad and Keyboard still work its only when the lid was closed they would lose function.
Reason for this function loss, IPD_PWR_EN from PMU (PMIC) 1.8v line dropping to 0v
This normally shuts on and off based on lid position but it seems to go low and stick low 0v on lid close.
This may be resolved with replacing the PMU but it may also be something beyond the PMU.
I found the easiest solution was to snag a 1v8 line from a secondary source to power these rails. I used 3v3_S2_EN line which is high all the time when lid is closed. This will cause I assume some power usage while the lid is closed (assuming minimal) but it solves the issue with the low IPD_PWR_EN being lost after lid close.
