W/Harness Inspection

Terminal and 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?






Power Circuit Inspection

Check voltage
1. IG "OFF" & Disconnect HO2S (B1/S1) connector.
2. IG "ON".
3. Measure voltage between power terminal of HO2S (B1/S1) heater harness connector and chassis ground.

Specification : B+





4. Is the measured voltage within specification?






Control Circuit Inspection

Check short to ground
1. IG "OFF" & Disconnect HO2S (B1/S1) connector.
2. Measure resistance between control terminal of HO2S (B1/S1) heater harness connector and chassis ground.

Specification : Infinite





3. Is the measured resistance within specification?





Check open in harness
1. IG "OFF" and disconnect HO2S (B1/S1) and ECM connector.
2. Measure resistance between control terminal of HO2S (B1/S1) heater harness connector and heater control terminal of ECM harness connector.

Specification : Approx. below 1 Ohm





3. Is the measured resistance within specification?