Component Inspection

Engine Control
P0131 HO2S Circuit Low Input(Bank 1 / Sensor 1) - Component Inspection

Component Inspection

1. Visually/physically inspect following items:
A. 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.
B. If contamination is evident on the HO2S, replace contaminated sensor and go to next step.
2. Warm up the engine to normal operating temperature and check that HO2S signal is active.
3. Connect Scantool and monitor the "O2 SNSOR VOLT. (B1/S1)" parameter on the Scantool data list.




4. Is sensor data near the specified value?
YES
> 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
> 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