O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1)
Powertrain Code · Medium
What does P0131 mean?
Low voltage from the upstream O2 sensor on bank 1, indicating a possible lean condition or sensor failure.
System: O2 Sensor
P0131 is a powertrain diagnostic trouble code indicating o2 sensor circuit low voltage (bank 1, sensor 1). This code is classified as medium severity, which means: schedule service — affects performance or emissions. We have vehicle-specific diagnostic data for 43 models below. Select your vehicle for tailored causes, symptoms, and repair cost estimates.
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.
See causes, symptoms, and repair costs for P0131 on specific vehicles: