Technical Definition:

O2 Circuit (Bank 1, Sensor 2) (See P2270, P2271)

Technical Description:

Possible Causes:

• Faulty O2 sensor leak in exhaust close to O2 sensor
• Short to voltage on O2 signal circuit
• Open in circuit resistance caused by corrosion in connector

Possible Symptoms:

O2 Sensor Circuit Malfunction Bank 1 Sensor 2

Possible Solutions:

• Replace the second oxygen sensor on bank 1
• Repair open or short in signal circuit
• Clean corrosion from connector

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty Rear Heated Oxygen Sensor Bank 1
– Rear Heated Oxygen Sensor Bank 1 harness is open or shorted
– Rear Heated Oxygen Sensor Bank 1 circuit poor electrical connection
– Inappropriate fuel pressure
– Faulty fuel injectors
– Intake air leaks may be faulty
– Exhaust gas leaks

Specific Makes:

– High Fuel Consumption
– Excessive Smoke from Exhaust