Engine-Codes - Honda - P2251 Honda

P2251 Honda Code - Rear Air/Fuel Ratio Sensor Bank 1 Sensor 1 VS Line High Voltage

- Code Popularity: 29,023 Views
- Repair Importance Level: 2/3
- Repair Difficulty Level: 2/3
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What are the Possible Causes of the DTC P2251 Honda?

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
  • Rear Air/Fuel Ratio Sensor Bank 1 Sensor 1 harness is open or shorted
  • Rear Air/Fuel Ratio Sensor Bank 1 Sensor 1 circuit poor electrical connection
  • Faulty Rear Air/Fuel Ratio Sensor Bank 1 Sensor 1
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How to Fix the DTC P2251 Honda?

Check the 'Possible Causes' listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector pins.

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What is the Cost to Diagnose the Code?

Labor: 1.0

The cost to diagnose the P2251 Honda code is 1.0 hour of labor. The diagnosis time and labor rates at auto repair shops vary depending on the location, make and model of the vehicle, and even the engine type. Most auto repair shops charge between $75 and $150 per hour.

What are Code Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)

What Does the P2251 Honda Code Mean?

The rear air/fuel ratio (A/F) sensor (bank 1, sensor 1) is installed in the exhaust manifold and detects oxygen content in the exhaust gas. The rear A/F sensor transmits a signal to the Powertrain Control Module (PCM), and it enables overall feedback control. The PCM controls fuel injection duration by comparing the target air/fuel ratio with the rear A/F sensor signal. When the VSB1 terminal voltage is more than a specified value for a predetermined time, the PCM detects a malfunction and stores a DTC.

P2251 Honda Code - Rear Air/Fuel Ratio Sensor Bank 1 Sensor 1 VS Line High Voltage

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