Many malfunctions in the electrical system are caused by poor harness(es) and terminals. Faults can also be caused by interference from other electrical systems, and mechanical or chemical damage.

Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.

Has a problem been found?

YES

Repair as necessary and go to "Verification of Vehicle Repair" procedure.

NO

Go to "Signal Circuit Inspection" procedure.

Ignition "OFF".

Disconnect HO2S connector.

Ignition "ON" & Engine "OFF".

Measure voltage between terminal 1 of the sensor harness connector and chassis ground.

Specification : Approx. 0V

Is voltage within the specification?

YES

▶ Go to "Component Inspection" procedure.

NO

▶ Repair as necessary and go to "Verification of Vehicle Repair" procedure.