The working holes and drainage holes are re-applied with silicone glue and then tested, there is no water leakage, and the cause of water entering through the drainage holes is ruled out.
There is no water leakage in the test after the silica gel is applied to the working hole and drainage hole again, and the cause of water inflow from the drainage hole is ruled out
The working hole and drain hole are reapplied with silica gel before testing that there is no water leakage, so as to eliminate the cause of water inflow from drain hole.