A10: Check For Short to 1B, 2A, 3A, 4B GND

With connectors EM015 and PI007 to PI014 disconnected, measure the insulation resistance between EM015/011 &, in turn, EM015/015, 016, 017, 018.

Is the resistance > 10M ohms?

Yes
Go to A11 A11: Check For Short to 1A, 2B, 3B, 4A GND

No
Repair the harness/connector (PI001/038, 033, 032, 035) and test the system for normal operation.