G12: Signal Ground 2 Continuity

With EM010 and EM014 disconnected, measure the resistance between EM014/004 and chassis ground EM008L.

Is the resistance < 0.5 ohms?

Yes
GO to G14, G14: Check For O2 Sensor Continuity

No
Inspect connector EM014 for corrosion, damage, or pushed back pin.
Inspect ground stud EM008L for corrosion or damage.
Inspect harness/splice EMS36 for damage.
Repair as required and reconnect plug(s).
GO to G13, G13: Stop