P0688 GMC
Electronic Control Module Power Relay Sense Circuit/Open
GMC
P0689 GMC
Electronic Control Module Power Relay Sense Circuit Low
P0686 GMC
Engine Control Module Power Relay Control Circuit Low
P0687 GMC
Engine Control Module Power Relay Control Circuit High
P0677 GMC
Cylinder 7 Glow Plug Circuit Fault
P0678 GMC
Cylinder 8 Glow Plug Circuit Fault
P0685 GMC
Engine Control Module Power Relay Control Circuit Open
P0675 GMC
Cylinder 5 Glow Plug Circuit Fault
P0676 GMC
Cylinder 6 Glow Plug Circuit Fault
P0673 GMC
Cylinder 3 Glow Plug Circuit Fault