P0138-O2 Sensor 2/2 Circuit Low: Notes

Fig 1: O2 Sensors Circuit Schematic

Courtesy of CHRYSLER LLC

1. 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.
2. Set Condition  : O2 Sensor voltage is less than 0.15 volt for approximately 5 seconds.

For a complete Powertrain Control Module Circuit Diagram, refer to SCHEMATICS AND DIAGRAMS .