P0145 – OBD-II DTC

OBD-II DTC P0145 – O2 Sensor Circuit High Voltage (Bank 1 Sensor 3)

DTC P0145 meaning

DTC P0145 refers to a diagnostic trouble code indicating a high voltage condition in the oxygen sensor circuit for Bank 1 Sensor 3. This sensor is responsible for monitoring the oxygen levels in the exhaust gases, which helps the engine control module (ECM) adjust the air-fuel mixture for optimal combustion. A high voltage reading suggests that the sensor may be malfunctioning or that there is an issue in the circuit.

DTC P0145 symptoms

Common symptoms associated with DTC P0145 may include:

  • Check Engine Light illuminated
  • Poor fuel economy
  • Rough engine idle
  • Increased emissions
  • Failed emissions test

DTC P0145 causes

Several factors can lead to the triggering of DTC P0145, including:

  • Faulty oxygen sensor
  • Wiring issues or damaged connectors in the sensor circuit
  • Short circuit to voltage in the sensor circuit
  • Corrosion or poor connections in the electrical system
  • ECM malfunction

DTC P0145 seriousness

DTC P0145 is considered a moderate to serious issue. While it may not cause immediate engine failure, it can lead to:

  • Increased fuel consumption
  • Higher emissions, potentially leading to legal issues
  • Long-term engine damage if not addressed

How to diagnose DTC P0145

To diagnose DTC P0145, follow these steps:

  1. Use an OBD-II scanner to confirm the code and check for any additional codes.
  2. Inspect the oxygen sensor and its wiring for visible damage or corrosion.
  3. Test the voltage at the oxygen sensor connector with a multimeter.
  4. Check for continuity in the wiring between the sensor and the ECM.
  5. Verify the ground connection for the sensor circuit.
  6. Replace the oxygen sensor if it is found to be faulty.

How to fix DTC P0145 step-by-step instructions

To fix DTC P0145, follow these steps:

  1. Gather necessary tools: OBD-II scanner, multimeter, and basic hand tools.
  2. Disconnect the battery to ensure safety while working on the electrical system.
  3. Locate Bank 1 Sensor 3 and inspect the sensor and wiring for damage.
  4. Test the sensor’s voltage output using a multimeter it should be within the manufacturer’s specifications.
  5. If the sensor is faulty, replace it with a new one.
  6. Repair any damaged wiring or connectors found during inspection.
  7. Reconnect the battery and clear the DTC using the OBD-II scanner.
  8. Take the vehicle for a test drive to ensure the code does not return.

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