P0146O2 Sensor Circuit No Activity Detected Bank 1 Sensor 3
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- Sensor 3 is a third oxygen sensor on bank 1, behind a second converter or converter brick. It only exists on some vehicles – documented for Jaguar Land Rover's 3.0 V6 supercharged (2013–2016, where sensor 2 is 'mid-cat' and sensor 3 'post-cat') and Ford systems that monitor part of the converter volume. P0146 means sensor 3 produces no voltage of its own and only the control module's bias voltage is seen, as for sensor 2 (P0140): GM evaluates a signal stuck in the 401–548 mV band, a high internal resistance or, with 1900 mV bias, an open circuit. No manufacturer document using exactly this code was found; Jaguar Land Rover lists only P0142–P0144 and P0147 for its sensor 3. When it fails, the control module stops the downstream trim and cannot evaluate the converter; there is no limp mode.
- What you may notice
- Check engine light on (usually after two drive cycles)
- Usually no noticeable change in driving
- Likely causes
- LikelySignal or ground wire open, connector off or corroded
- PossibleSensor heater failed, sensor never becomes active
- PossibleSensor worn out (no longer produces voltage)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Easy · Often possible to do yourself.Typical cost: €50 – €250
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.