A9: Signal Ground 1 Continuity

With EM010 & EM014 disconnected, measure the resistance between EM010/023 & chassis ground EM008L

Is the resistance < 0.5 Ohms?

Yes
Go to A10 A10: Signal Ground 2 Continuity

No
Inspect connector EM010 for corrosion, damage, or pushed back pin
Inspect ground stud EM008L for corrosion
Repair as required, harness, splice EMS36, connector or ground; reconnect plug(s)
Go to A11 A11: Stop