P0146: O2 Sensor Circuit No Activity Detected — Bank 1 Sensor 3
What to do
No driveability impact. Have the connector inspected before the sensor is replaced.
What this code means
The bank 1 third sensor signal is flat. Corroded connectors and severed underfloor wiring lead the causes; check for an accompanying heater code, since an unheated sensor at the far end of the exhaust may simply never get warm enough to switch.
Likely causes
Start here
- Corroded or loose connector · easy
- Open circuit in sensor wiring · moderate
- Faulty oxygen sensor · easy
Less common
- Failed oxygen sensor heater element · easy
- Road damage to underfloor wiring · moderate
Symptoms
Components involved
Information, not instruction
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Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
Community experience
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