P2278 Code - O2 Sensor Signals Swapped Bank 1 Sensor 3/Bank 2 Sensor 3
Quick Answer
Diagnostic trouble code (DTC) P2278 indicates that the oxygen sensor signals for Bank 1 Sensor 3 and Bank 2 Sensor 3 have been swapped. Common causes include Wiring harness or connector damage, Faulty oxygen sensor(s), ECM software malfunction. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
- What it means
- P2278 indicates O2 Sensor Signals Swapped Bank 1 Sensor 3/Bank 2 Sensor 3.
- Common causes
- Common causes include Wiring harness or connector damage, Faulty oxygen sensor(s), ECM software malfunction.
- Severity
- Moderate - service should be scheduled soon.
- Can I drive?
- The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
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Code P2278 Description
Diagnostic trouble code (DTC) P2278 indicates that the oxygen sensor signals for Bank 1 Sensor 3 and Bank 2 Sensor 3 have been swapped. Oxygen sensors, also known as O2 sensors, are crucial components in a vehicle's emissions control system. They measure the amount of oxygen in the exhaust gases and provide feedback to the engine control module (ECM) to adjust the air-fuel ratio for optimal combustion. Bank 1 refers to the side of the engine where cylinder 1 is located, while Bank 2 refers to the opposite side in V-type engines.
Common Causes of P2278
- Wiring harness or connector damage
- Faulty oxygen sensor(s)
- ECM software malfunction
- Exhaust leaks near the sensors
- Crossed sensor wiring during previous repairs
Symptoms of P2278
- Decreased fuel efficiency
- Rough idling or stalling
- Check Engine Light illuminated
- Poor acceleration or engine performance
- Increased emissions
How to Fix P2278
- Diagnose the issue by using a scan tool to verify the specific oxygen sensor signals that are swapped.
- Inspect the wiring harness and connectors for any damage or corrosion. Repair or replace as necessary.
- Check the oxygen sensors for proper operation and replace any faulty sensors.
- Clear the DTC and retest the vehicle to ensure the issue has been resolved.
- Perform a road test to confirm that the engine performance has returned to normal.
Cost to Fix P2278
The typical repair costs for addressing DTC P2278 can vary depending on the extent of the issue and the specific components that need to be replaced. Generally, the cost of replacing an oxygen sensor can range from $100 to $300 per sensor, including parts and labor. Additional costs may be incurred if wiring repairs or ECM reprogramming are required. It is recommended to consult with a professional mechanic or dealership to get an accurate estimate based on the vehicle's make and model, as well as the local labor rates. Keep in mind that diagnostic time and labor rates can vary between auto repair shops.
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Code P2278 Information for Specific Makes
- P2278 Dodge — O2 Sensor Signals Swapped Bank 1 Sensor 3/Bank 2 Sensor 3
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