P0151-O2 Sensor 2/1 Circuit Low: Notes
- When Monitored : With the engine running between 1000 and 2000 RPM, engine load between 15% to 50%, closed loop mode, the three way catalytic converter temperature is greater than 380°C (716°F), and the O2 sensor heater must be ON for at least 220 seconds to enable the signal inactive portion of the test.
- Set Condition : O2 Sensor voltage is less than 0.15 volt for approximately 5 seconds. Signal stays at center: The O2 Sensor voltage stays between 0.4 and 0.6 volt for more than approximately 15 seconds after the O2 Sensor heater has been ON for at least 220 seconds.
| Possible Causes |
| O2 SENSOR SIGNAL CIRCUIT OPEN |
| O2 SENSOR SIGNAL CIRCUIT SHORT TO GROUND |
| O2 SENSOR GROUND CIRCUIT OPEN |
| ENGINE EXHAUST LEAK |
| O2 SENSOR |
| POWERTRAIN CONTROL MODULE |
For a complete Powertrain Control Module Circuit Diagram, refer to SCHEMATICS AND DIAGRAMS .