Terminal and Connector Inspection

Many malfunctions in the electrical system are caused by poor harness and terminals.
Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.
Thoroughly check all connectors (and connections) for looseness, bending, corrosion, contamination, deterioration, and/or damage.
Has a problem been found?

Fig 1: Upstream O2 Sensor Circuit Diagram (A/T)
Courtesy of KIA MOTORS AMERICA, INC.

Fig 2: Upstream O2 Sensor Circuit Diagram (M/T)
Courtesy of KIA MOTORS AMERICA, INC.

YES
- Repair as necessary and go to "VERIFICATION OF VEHICLE REPAIR " procedure.
NO
- Go to "SIGNAL CIRCUIT INSPECTION " procedure.