What it means
Bank 2 counterpart to P2246. The reference voltage at bank 2, sensor 1 is above the upper threshold, usually due to a short to positive or connector leakage.
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 oxygen sensor on the engine’s second cylinder bank; its reference-voltage circuit supports the sensor’s air-fuel measurement. The control module sets this code when that circuit reads higher than its allowed range, which can happen with a short to positive or leakage at the connector.
Common causes
Most likely first.
- Reference line shorted to positive
- Connector corroded with leakage
- Supply wire pinched against B+ source
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
How to diagnose it
- Review freeze-frame data and fuel-trim or oxygen-sensor codes to see how the engine was operating when Bank 2 Sensor 1’s reference voltage went high.
- Inspect the Bank 2 Sensor 1 connector and harness for corrosion, moisture, damaged insulation, or contact with a power feed.
- Use the wiring diagram to identify the reference-voltage wire and check for a short to positive with the sensor disconnected as specified by the manufacturer.
- Check connector terminals for leakage or contamination and verify circuit continuity using the manufacturer’s procedure.
- If the circuit is sound, test Bank 2 Sensor 1 and the module circuit following the manufacturer’s diagnostic procedure.
Common fixes
- Clean and dry the Bank 2 Sensor 1 connector and secure its terminals.
- Repair a reference wire shorted to positive or replace the damaged harness section.
- Replace Bank 2 Sensor 1 if testing confirms an internal fault.
- Repair the module circuit only if wiring and sensor tests identify it as the source.
Can I keep driving?
You can usually drive cautiously if the engine runs normally, but fuel use and emissions may rise because the module may not control fueling accurately from Bank 2 Sensor 1. Avoid prolonged driving if it runs roughly or hesitates.
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.