I suspect that the outdoor unit of Haier air conditioner at home was not grounded when it was installed. This is the photo I took. Please take a look at it for me. Thank you.

The grounding of the outdoor unit of the air conditioner is connected to the indoor unit through a cable, and then the indoor unit is connected to the ground wire through a three-eye socket. The key is to see whether the grounding terminal of your socket is reliably grounded. Under normal circumstances, the outdoor unit does not repeat independent grounding.

The two black cables in your picture are a power line, including a ground wire, and a signal line, that is, a control line.