P0042
HO2S Heater Control Circuit Bank 1 Sensor 3
Generic code
Fuel and Air Metering
Medium severity
Moderate repair
Free on OBD DashX
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What P0042 means
- The fault code P0042 indicates there is an issue with the heating circuit of the oxygen sensor in bank 1, sensor 3. This may cause the engine to run poorly, reduce fuel efficiency, or not start at all.
Possible symptoms
- Illuminated check engine light
- Reduced fuel efficiency
- Poor engine performance
- Engine may not start
Possible causes
- Failed oxygen sensor heating element
- Damaged or corroded wiring or connections in the circuit
- Failed engine control module (ECM)
Related parts
- Heated Oxygen Sensor: This is one of the parts that fails very commonly. It measures the amount of oxygen to ensure proper combustion. Problems in the Oxygen Sensor lead to poor fuel economy
Possible solutions
- Replace the oxygen sensor
- Check and repair any damaged wiring or connections in the circuit
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0042 on OBD DashX
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