P0051 Lexus Code - Oxygen Sensor Heater Control Circuit Low Bank 2 Sensor 1
Quick Answer
Air-Fuel Ratio (A/F) sensor need to reach a minimum operating temperature of 1200 degrees F to produce an accurate voltage signal. Common causes include Faulty Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1, Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1 harness is open shorted to ground, Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1 circuit poor electrical connection. 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
- P0051 Lexus indicates Oxygen Sensor Heater Control Circuit Low Bank 2 Sensor 1.
- Common causes
- Common causes include Faulty Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1, Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1 harness is open shorted to ground, Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1 circuit poor electrical connection.
- 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.
Code P0051 Lexus Description
In order to achieve the require temperature, a heater element is included inside the air-fuel ratio sensor. The ECM controls the air-fuel ratio sensor heater element based on signals from the engine coolant temperature and engine load. The ECM controls the heater element circuit by allowing current flow to ground.
The ECM monitors the voltage signal received through the heater element circuit and determines the state of the circuit by comparing the voltage detected with the factory specifications.
What are the Possible Causes of the DTC P0051 Lexus?
- Faulty Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1
- Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1 harness is open shorted to ground
- Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1 circuit poor electrical connection
- Air-Fuel Ratio (A/F) Sensor Bank 2 Sensor 1 circuit fuse
- Faulty Engine Control Module (ECM)
How to Fix the DTC P0051 Lexus?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
2004-2005 Lexus ES 330 Factory Service Bulletin OBDII Code P0051
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0051 Lexus code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Frequently Asked Questions about P0051 Lexus Code
1. What are the common symptoms of OBDII code P0051 in a Lexus?
- Common symptoms include decreased fuel efficiency, rough idling, engine misfires, and the illumination of the Check Engine Light.
2. What does the OBDII code P0051 in a Lexus indicate?
- The code P0051 indicates an issue with the oxygen sensor heater control circuit low in Bank 2 Sensor 1.
3. What are the possible causes of OBDII code P0051 in a Lexus?
- Possible causes include a faulty oxygen sensor, damaged wiring or connectors, a blown fuse, or a problem with the engine control module (ECM).
4. How can I diagnose the OBDII code P0051 in my Lexus?
- Diagnose the code by checking the oxygen sensor heater circuit for continuity, inspecting wiring for damage, and verifying proper voltage to the sensor.
5. How can I repair OBDII code P0051 in a Lexus?
- Repair options include replacing the oxygen sensor, repairing damaged wiring or connectors, checking and replacing fuses if necessary, and resetting the ECM.
6. Can I drive my Lexus with OBDII code P0051?
- It is generally safe to drive the vehicle with this code, but it is recommended to address the issue promptly to prevent potential damage to the catalytic converter.
7. How much does it cost to repair OBDII code P0051 in a Lexus?
- The cost of repairing this code can vary depending on the underlying issue, but it typically ranges from $200 to $500 for parts and labor.
8. Will resetting the Check Engine Light resolve OBDII code P0051 in a Lexus?
- Resetting the Check Engine Light may temporarily remove the warning, but the underlying issue causing the code will persist until properly diagnosed and repaired.
9. Is it possible to prevent OBDII code P0051 from occurring in my Lexus?
- Regular maintenance, such as checking and replacing oxygen sensors as recommended, can help prevent the occurrence of code P0051 in your Lexus.
10. How long does it take to repair OBDII code P0051 in a Lexus?
- The repair time for this code can vary depending on the exact cause and the availability of parts, but it typically takes 1-2 hours at a professional repair shop.
Discuss the causes and fixes for P0051 Lexus OBDII Code
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Hi, I own a 05 Lexus GX470, I have a Christmas tree in my dash, and the codes I'm getting form the OBDC reader are P0031 and P0051. I checked all the wires for voltage and resistance, and they're good. Replaced all 4 oxygen sensors wirh genuine OEM, replaced the ECU twice, each time with a different one but same part number as the original. I have a whole year trying to resolve this problem to no avail. The vehicle, currently has 154k miles in the speedometer. I have not have any other mechanical problem besides this one. I just red somewhere in this site to check for the relay and the fuse. Couldn't find either one in my vehicle, or perhaps they have a different name on the fuse box cover.
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Both, the A/F Heater Relay and A/F Heater Fuse, are in the fuse box in the engine compartment.
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If the fuse, relay and sensors are OK, then the next step is to check the wires from the sensor to the ECU.
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I could be wrong, but my logical view on the P0051 code is that if the #6 A/F relay or fuse were related to the P0051 fault code, it stands to reason that both or all AF mix "Short and long term Fuel trim sensors" would be throwing that code. The reason for this logic is that B1/S1 and B2/S2 are powered by the same #6 Relay and AF Fuse so B1/S1 fault code should also be coming up in the DTCs?
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No, both Air Fuel Ratio Sensors (A/F or Front Sensors) are powered by the 'A/F Relay' (#6), and the Rear Heater Oxygen Sensors are powered by the 'EFI Relay' (#8). Therefore, if the A/F Relay is faulty, it could trigger the P0031 and P0051 engine codes.
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