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At PM_SLP_S3_R_L are only U8180 and Q8131connected.
If you have 1.2V there and 3.3V at PM_SLP_S3_L, guess what???
Bad U8180, or R8178; less probably bad Q8131...
Great! Have changed U8180 though, but I guess must be a bad one still. I will try another U8180 tomorrow and give you feed back on it... have a good one champ.