P0155 – OBD-II DTC

OBD-II DTC P0155 – O2 Sensor Circuit No Activity Detected (Bank 2 Sensor 1)

DTC P0155 meaning

DTC P0155 refers to a diagnostic trouble code indicating that the oxygen sensor circuit for Bank 2 Sensor 1 is not functioning properly. This sensor is responsible for monitoring the oxygen levels in the exhaust gases before they enter the catalytic converter. When the Engine Control Module (ECM) detects that there is no activity from this sensor, it triggers the P0155 code.

DTC P0155 symptoms

Common symptoms associated with DTC P0155 may include:

• Check Engine Light illuminated
• Decreased fuel efficiency
• Rough engine idle
• Increased emissions
• Potential engine performance issues

DTC P0155 causes

Several factors can lead to the P0155 code, including:

• Faulty oxygen sensor
• Wiring issues or damaged connectors in the O2 sensor circuit
• Exhaust leaks near the sensor
• Faulty Engine Control Module (ECM)
• Corrosion or poor connections in the sensor circuit

DTC P0155 seriousness

The seriousness of DTC P0155 can vary, but it is generally considered a moderate issue. If left unaddressed, it can lead to:

• Increased fuel consumption
• Higher emissions, potentially failing emissions tests
• Long-term damage to the catalytic converter

How to diagnose DTC P0155

To diagnose DTC P0155, follow these steps:

1. Use an OBD-II scanner to confirm the P0155 code and check for any additional codes.
2. Inspect the oxygen sensor and its wiring for any visible damage or corrosion.
3. Check the sensor’s voltage and ground connections using a multimeter.
4. Test the oxygen sensor’s response by monitoring its voltage while the engine is running.
5. Inspect for any exhaust leaks that may affect sensor readings.

How to fix DTC P0155 step-by-step instructions

To fix DTC P0155, follow these steps:

1. Disconnect the battery to ensure safety while working on the vehicle.
2. Inspect and repair any damaged wiring or connectors related to the oxygen sensor.
3. If the oxygen sensor is faulty, replace it with a new one.
4. Ensure all connections are secure and free from corrosion.
5. Reconnect the battery and clear the DTC using an OBD-II scanner.
6. Start the engine and monitor for any reoccurrence of the code.

How to erase DTC P0155

To erase DTC P0155, follow these steps:

1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
2. Turn on the ignition without starting the engine.
3. Navigate to the option to clear or erase trouble codes on the scanner.
4. Confirm the action to erase the codes.
5. Disconnect the scanner and start the engine to ensure the code does not return.

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