Motherboard fitted is a NM-C431 REV 1.0.
This system is still under the 2 year Australian Consumer Law warranty so motherboard is going to be swapped out. Putting this here in case someone else sees the same fault(s) in future. No schematics appear to be currently available (board is dated 2019).
First fault is that system will not power on from the battery, but will charge it. The power button is on a daughterboard, and measures 300mv on its centre pin. There is 3.3V supply present on the board though.
When USB C is connected, the unit powers on with no interaction with power button. There is about 700mV on it in this case. It boots into Windows, but then powers off. This is approx 10 seconds or so after power on. This happens regardless of whether you're in Windows, or BIOS.
I was able to take a BIOS dump, and that appears ok. It has 14.0 ME FW on it. Do these symptoms sound like an issue with the PMC FW at all? I did some probing around and don't see any shorted FET's.
It does have a BGA EC fitted, can't work pinouts to dump it without a schematic. Beginning to think there is something odd in that area since of the odd volts noted at the power button.
This system is still under the 2 year Australian Consumer Law warranty so motherboard is going to be swapped out. Putting this here in case someone else sees the same fault(s) in future. No schematics appear to be currently available (board is dated 2019).
First fault is that system will not power on from the battery, but will charge it. The power button is on a daughterboard, and measures 300mv on its centre pin. There is 3.3V supply present on the board though.
When USB C is connected, the unit powers on with no interaction with power button. There is about 700mV on it in this case. It boots into Windows, but then powers off. This is approx 10 seconds or so after power on. This happens regardless of whether you're in Windows, or BIOS.
I was able to take a BIOS dump, and that appears ok. It has 14.0 ME FW on it. Do these symptoms sound like an issue with the PMC FW at all? I did some probing around and don't see any shorted FET's.
It does have a BGA EC fitted, can't work pinouts to dump it without a schematic. Beginning to think there is something odd in that area since of the odd volts noted at the power button.