P0146 O2 Sensor Circuit No Activity Detected Bank 1 Sensor 3

Definition: The P0146 code indicates that the oxygen sensor circuit for bank 1, sensor 3 is not showing any activity. This means that the Engine Control Module (ECM) has detected no signal from this specific oxygen sensor.

p0146 – O2 Sensor Circuit No Activity Detected Bank 1 Sensor 3

Typical Severity: Moderate

Common Causes

P0146 – O2 Sensor Circuit No Activity Detected Bank 1 Sensor 3

Common causes of this OBD2 code include:

• Faulty oxygen sensor
• Open or short in the wiring harness to the sensor
• Poor electrical connection at the oxygen sensor
• Exhaust system leaks
• Fuel pressure too high or too low
• Vacuum leaks

Common Misdiagnosis

OBD2 Code: P0146

Description: O2 Sensor Circuit No Activity Detected Bank 1 Sensor 3

Common Misdiagnosis: Replacing the oxygen sensor without checking for wiring issues or exhaust leaks.

Common Diagnostic Steps

OBD2 Code: P0146

Description: O2 Sensor Circuit No Activity Detected Bank 1 Sensor 3

• Verify the code with an OBD-II scanner and clear it to see if it returns.
• Inspect the wiring and connectors for damage or corrosion at Bank 1 Sensor 3.
• Check for exhaust leaks near the sensor that might affect its operation.
• Test the oxygen sensor’s voltage and resistance using a multimeter to ensure it’s within specifications.
• Examine the vehicle’s PCM (Powertrain Control Module) for any software updates or known issues related to this code.
• If applicable, check for any vacuum leaks that could impact sensor readings.
• If all else fails, replace the oxygen sensor at Bank 1 Sensor 3 and retest.