Error 4sns/1/40000001:VPOR-0.003. Water Damage, acting up?

Some sort of Voltage problem power bus ''(from your description you should have already surmised this)'' . Sorry I can't be more specific.

4sns is at the beginning of every sensor error the data at the end of the error code points to what hardware that is out of spec, and, numbers usually represent how far out of spec the hardware is.

Did you run the diagnostic with the magsafe connected or on battery only? Some power errors come up if the unit is not plugged into the mains during the test (or if in your case the main power supply is unstable).

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