P2276 O2 Sensor Signal Biased/Stuck Lean (Bank 2, Sensor 3)

P2276 needs three oxygen sensors on bank 2, so it only occurs on V or flat engines whose second bank carries a front, a mid-catalyst and a post-catalyst sensor. It reports that the post-catalyst sensor of bank 2 does not reach a rich reading. No manufacturer publishes a threshold for this exact code; Jaguar Land Rover lists it, with P2277 and the heater and circuit codes of that sensor, for the 2014 to 2016 3.0 supercharged V6 in the LR4, Range Rover and Range Rover Sport, where water on the hot element cracked the sensor. Ford's monitor runs the same switch-point test on sensors 2 and 3 and fails a rich peak below 0.42 V. CARB requires secondary sensors to be checked for sufficient output. If bank 1 is fault-free, compare both third sensors and look for an exhaust leak on bank 2.

Likely causes

Symptoms

• Malfunction indicator lamp on
• No noticeable change in driveability

Repair estimate

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

Related codes

References: static.nhtsa.gov, newtonnet.co.uk, law.cornell.edu.