W/Harness Inspection

P0140 O2 Sensor Circuit No Activity Detected (Bank 1 / Sensor 2)

Inspection/Repair - W/Harness Inspection

Terminal & Connector Inspection

1. 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.
2. Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage.
3. Has a problem been found?






Signal Circuit Inspection

Check Open in signal circuit
1. IG KEY "OFF".
2. Disconnect HO2S (S2) connector and ECM connector.
3. Measure the voltage between signal terminal of HO2S (S2) harness connector and chassis ground.

Specification : below 1 Ohms




4. Is the measured resistance within specification?






Ground Circuit Inspection

Check Open in ground circuit
1. IG KEY "OFF".
2. Disconnect HO2S (S2) connector.
3. Measure resistance between ground terminal of HO2S (S2) and chassis ground.

Specification : below 1 Ohms




4. Is the measured resistance within specification?