Component Inspection
- Visually/physically inspect following items:
- Inspect the front HO2S for any silicon contamination. This contamination will be indicated by a white powdery coating and this will result in a but false voltage signal
- If contamination is evident on the HO2S, replace contaminated sensor and go to next step.
- Warm up the engine to normal operating temperature and check that HO2S signal is active.
- Connect GDS and monitor the "O2 SNSR VOLT. (B1/S1)" parameter on the GDS data list.
Test Condition : Engine "ON" & In Closed loop mode
Specification : - Normal HO2S (B1S1) value with engine warm-up and idling : Approx. 1.5~2.0V
- Signal decreases with rich air/fuel mixture and increases with lean air/fuel mixture
- Voltage at Fuel cutoff mode : Approx. 3.0~4.0V
- Is sensor data near the specified value?
YES
- Check for poor connection between PCM 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
- 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.