P2240 - O2 SENSOR POSITIVE CURRENT CONTROL CIRCUIT / OPEN BANK 2 SENSOR 1

Setting DTC P2240 OBDII code indicates that the Powertrain Control Module (PCM) has encountered a positive current inconsistency from the Oxygen sensor (O2) sensor number 1 on bank 2. This sensor is located in front of the Catalytic Converter (TWC) and its positive current control circuit is a low voltage circuit.

To monitor the amount of oxygen that is present in the exhaust of each bank of the engine, the PCM uses the input data from the O2 Sensors. In addition, this information is used to check that the TWC is working properly.

The voltage signal outputs from the Oxygen Sensors are lower when there is a considerable amount of oxygen in the exhaust. But these voltage signals are higher when there is less oxygen in the exhaust. In case an out-of-range voltage is detected, the fault code P2240 OBD2 is set.

• Check Engine light illuminated.
• Reduced fuel efficiency.
• Reduced engine power.
• Ignition fault codes set.

The reasons for setting the P2240 OBDII diagnostic code are:

• Oxygen Sensor wires or connectors may be disconnected, worn, or burned.
• The Oxygen Sensor may be defective.

To troubleshoot the P2240 OBD2 error code you should consider the following:

• Inspect the cables and connectors that are associated with the Oxygen Sensor. You should repair or replace the cables that are in bad condition.
• With a DVOM check the resistance between the positive current control circuit and a ground circuit. If you detect continuity, you should replace the sensor.
• If the O2 Sensor shows battery voltage, use the DVOM to obtain live data at the sensor connector. If the output data remains the same, the O2 Sensor has a short internally. Replace it.