Component Inspection

Component Inspection

1. Visually/physically inspect the following items:
-Inspect the front HO2S for any silicon contamination. This contamination will be indicated by a white powdery coating on the portion of the sensor exposed to the exhaust stream and this will result in a but false (high) voltage signal
-If contamination is evident on the HO2S, fix the source of the sensor contamination before replacing the sensor to prevent future contamination. Go to "Verification of Vehicle Repair" procedure.
2. Warm up the engine to normal operating temperature and let it idle.
3. Connect Scantool and monitor the O2 SENSOR VOL.-B1/S1 parameter on the Scantool data list
A. Specification :Verify signal is switching from rich (above 0.45V) to lean (below 0.45V) a minimum of 3 times in 10 seconds (voltage will vary between 0.1 and 0.9V) at idle.
4. Is sensor switching properly ?
YES
1) Check for poor connection between ECM and component: backed out terminal, improper mating, broken locks or poor terminal to wire connection. Repair as necessary and go to "Verification of Vehicle Repair" procedure
NO
1) Check HO2S for contamination, deterioration, or damage. Substitute with a known-good HO2S and check for proper operation. If the problem is corrected, replace HO2S and then go to "Verification of Vehicle Repair" procedure