What it means
The trim adjustment for the pumping current of the intake air oxygen sensor on bank 2 reports a circuit open condition. Wide-band lambda regulation on the intake side is impaired.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The bank 2 intake-air oxygen sensor uses a wide-band pump cell, and its pumping-current trim circuit lets the control module adjust how that cell operates. P2AE9 sets when the module detects an open in this bank 2 trim circuit, so the sensor’s intake-side lambda regulation may be impaired.
Common causes
Most likely first.
- Open in pump current wire
- Internal open in pump cell
- Pin pushed back out of connector body
Symptoms
- Check engine light on
- Increased fuel consumption
- Possible rough idle or hesitation
- Failed emissions test
How to diagnose it
- Record freeze-frame data and inspect bank 2 intake-air sensor readings and fuel corrections for changes associated with the fault.
- Identify the bank 2 intake-air oxygen sensor from vehicle service information and inspect its connector for a pushed-back pin or incomplete seating.
- Inspect the trim-circuit wiring from the bank 2 sensor connector for breaks, chafing, heat damage, or a loose splice.
- Use the manufacturer's wiring diagram and procedure to check continuity through the trim circuit and its terminals for an open.
- If the wiring and connections pass, test the bank 2 sensor pump cell and trim circuit as specified by the manufacturer for an internal open.
Common fixes
- Reseat the bank 2 sensor connector and any displaced terminal.
- Repair a broken or damaged pumping-current trim wire.
- Replace a loose or damaged connector terminal.
- Replace the bank 2 intake-air oxygen sensor if its internal trim or pump-cell circuit is open.
Can I keep driving?
If the engine runs normally, a short, gentle drive is usually possible, though fuel economy and emissions performance may deteriorate. Avoid longer trips if rough idle or hesitation appears.
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.