Chosen Solution

Can anyone tell me the circuit for the power ribbon. I want to test if the power button is electrically doing what it should - I assume that when it is pressed it creates a short between two of the contacts on the end of the ribbon connector. Can someone confirm that and tell me which two are shorted or open circuited if it works the other way. Thanks

Based on the schematic, when the power button is pressed, the GPIO_BTN_ONOFF_L line is brought to a LOW condition (brought to ground). That sends a signal to the PMIC. The line does go through a filter (L2613), resistor (R2613) and it is clamped by a diode (DZ2613) on the logic board so any one of those components could be causing issues.