P0140

O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 2)

Powertrain Code · Medium

What does P0140 mean?

The downstream O2 sensor on bank 1 shows no switching activity.

System: O2 Sensor

P0140 is a powertrain diagnostic trouble code indicating o2 sensor circuit no activity detected (bank 1, sensor 2). This code is classified as medium severity, which means: schedule service — affects performance or emissions.

Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your vehicle.