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 "Ground Circuit Inspection" procedure.

Ignition "OFF"

Disconnect HO2S and ECM connectors.

Measure resistance between terminals 2 of the HO2S harness connector and 22 of the ECM harness connector.

Specification : Approx. 0Ω

Is resistance within the specification?

YES

▶ Go to "Signal circuit inspection" procedure.

NO

▶ Repair open in the ground circuit and go to "Verification of Vehicle Repair" procedure

Measure resistance between terminals 1 of the HO2S harness connector and 16 of the ECM harness connector.

Specification : Approx. 0Ω

Is resistance within the specification?

YES

▶ Go to "Component Inspection" procedure.

NO

▶ Repair open in the ground circuit and go to "Verification of Vehicle Repair" procedure.