What it means
The positive-current control circuit for the oxygen sensor at Bank 2 Sensor 1 is open or malfunctioning. This circuit is used with certain oxygen sensor designs.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Bank 2 Sensor 1 is the upstream wide-band oxygen sensor for the engine's second bank, and it provides exhaust mixture feedback for fuel control. P2240 sets when the controller detects an open or malfunction in this sensor's positive pumping-current control path.
Common causes
Most likely first.
- Pumping current line open on bank 2
- Bank 2 wide-band sensor failed
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
How to diagnose it
- Review freeze-frame and live data for Bank 2 Sensor 1 to determine when the fault occurred and whether its readings are absent or implausible.
- Inspect the upstream Bank 2 Sensor 1 harness and connector for heat damage, chafing, corrosion, or loose pins.
- Check for an exhaust leak near the Bank 2 Sensor 1 mounting point that could affect its readings.
- Using the wiring diagram, test continuity in the positive pumping-current wire from the Bank 2 Sensor 1 connector toward the control module.
- If the wiring and connector are intact, test the Bank 2 wide-band sensor and related circuits using the manufacturer's procedure.
Common fixes
- Reconnect or repair a loose or damaged Bank 2 Sensor 1 connector.
- Repair an open or heat-damaged positive pumping-current wire on Bank 2 Sensor 1.
- Repair an exhaust leak close to the upstream Bank 2 sensor.
- Replace Bank 2 Sensor 1 if testing confirms an internal sensor failure.
Can I keep driving?
A short, gentle drive may be possible if the engine runs normally, but avoid prolonged trips and hard acceleration. Faulty upstream feedback on Bank 2 can increase fuel use and emissions; stop and investigate promptly if the engine starts running roughly.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.