OBD-II DTC P0133 – O2 Sensor Circuit High Voltage (Bank 1 Sensor 1)
DTC P0133 meaning
DTC P0133 refers to a diagnostic trouble code indicating a high voltage condition in the oxygen sensor circuit for Bank 1 Sensor 1. This sensor is typically located before the catalytic converter and is responsible for monitoring the oxygen levels in the exhaust gases. A high voltage reading suggests that the sensor is detecting an excessive amount of oxygen, which can lead to improper air-fuel mixture adjustments by the engine control module (ECM).
DTC P0133 symptoms
Common symptoms associated with DTC P0133 may include:
- Check Engine Light illuminated
- Poor fuel economy
- Rough engine idle
- Increased emissions
- Loss of engine power
DTC P0133 causes
Several factors can lead to the occurrence of DTC P0133, including:
- Faulty oxygen sensor
- Wiring issues or damaged connectors in the O2 sensor circuit
- Exhaust leaks before the sensor
- Contaminated or damaged sensor
- ECM malfunction
DTC P0133 seriousness
DTC P0133 is considered a moderate to serious issue. If left unaddressed, it can lead to:
- Increased fuel consumption
- Potential damage to the catalytic converter
- Failing emissions tests
- Overall engine performance degradation
How to diagnose DTC P0133
To diagnose DTC P0133, follow these steps:
- Use an OBD-II scanner to confirm the presence of the P0133 code.
- Inspect the oxygen sensor and its wiring for any visible damage or corrosion.
- Check for exhaust leaks near the sensor.
- Test the voltage output of the oxygen sensor using a multimeter.
- Compare the readings to manufacturer specifications.
- Inspect the ECM for any faults or updates.
How to fix DTC P0133 step-by-step instructions
To fix DTC P0133, follow these steps:
- Disconnect the battery to ensure safety.
- Inspect and repair any damaged wiring or connectors in the O2 sensor circuit.
- If the oxygen sensor is faulty, replace it with a new one.
- Check for and repair any exhaust leaks that may affect sensor readings.
- Reconnect the battery and clear the DTC using an OBD-II scanner.
- Start the engine and monitor for any reoccurrence of the code.
How to erase DTC P0133
To erase DTC P0133, follow these steps:
- Connect an OBD-II scanner to the vehicle’s diagnostic port.
- Turn on the ignition without starting the engine.
- Navigate to the “Erase Codes” or “Clear DTCs” option on the scanner.
- Confirm the action to clear the trouble codes.
- Disconnect the scanner and start the engine to ensure the code does not return.