P0155
O2 Sensor Heater Circuit Malfunction Bank 2 Sensor 1
Generic code
Fuel and Air Metering
Medium severity
Moderate repair
Free on OBD DashX
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What P0155 means
- The P0155 fault code indicates that there is a problem with the heater circuit in the Oxygen (O2) sensor for Bank 2 Sensor 1. This malfunction may cause the engine to lose power and run poorly, and it may also fail to pass emissions testing.
Possible symptoms
- Illuminated check engine light
- Decreased fuel economy
- Rough idling or stalling
- Failed emissions testing
Possible causes
- Failed Oxygen (O2) sensor (Bank 2 Sensor 1)
- Damaged wiring or connections in the circuit associated with O2 Sensor in Bank 2 Sensor 1 (Check Fuse too)
- Corrosion or loose connections in the sensor
- Faulty Engine Coolant temperature sensor (or the associated circuit)
- Failed Engine control module (ECM)
Related parts
- 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 (O2) sensor
- Check and repair any damaged wiring or connections or Fuse
- Clean or tighten any loose or corroded connections
- Replace the engine control module (ECM) if necessary
Free on OBD DashX
P0155 on OBD DashX
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