Unable to Activate Shutdown message (BB_CPU?)
I have accumulated quite a few iphones 7/7+ which i could not start due to message Unable to Activate Shutdown. Initially I thought it could be BB_CPU problem but usually it happens after attempted Audio IC job and the phone still boot but does not show IMEI/Modem Firmware. In that case I just re-ball BB_CPU.
But the phones at hand with this error message have not been opened before so I am confused. perhaps more experienced micro solderers could shed some light? Thanks.