P0043 Nissan Code - Heated Oxygen Sensor 3 Heater Control Circuit Low
Quick Answer
The P0043 diagnostic trouble code (DTC) for Nissan vehicles specifically refers to an issue with the Heated Oxygen Sensor (HO2S) 3 Heater Control Circuit being detected as low. Common causes include Faulty Heater Element: The most common cause of this code is a malfunctioning heater element within the HO2S 3 sensor, Wiring Issues: Damaged or corroded wiring connections leading to the sensor can also trigger this code, ECM Malfunction: A malfunctioning engine control module (ECM) can also cause issues with the heater control circuit. 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
- P0043 Nissan indicates Heated Oxygen Sensor 3 Heater Control Circuit Low.
- Common causes
- Common causes include Faulty Heater Element: The most common cause of this code is a malfunctioning heater element within the HO2S 3 sensor, Wiring Issues: Damaged or corroded wiring connections leading to the sensor can also trigger this code, ECM Malfunction: A malfunctioning engine control module (ECM) can also cause issues with the heater control circuit.
- 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 P0043 Nissan Description
The P0043 diagnostic trouble code (DTC) for Nissan vehicles specifically refers to an issue with the Heated Oxygen Sensor (HO2S) 3 Heater Control Circuit being detected as low. The HO2S is a crucial component of the vehicle's emissions control system, responsible for monitoring the oxygen levels in the exhaust gases to ensure proper fuel mixture for optimal combustion. The heater control circuit is designed to reach and maintain a specific temperature in the sensor to ensure accurate readings.
Common Causes of P0043 Nissan
- Faulty Heater Element: The most common cause of this code is a malfunctioning heater element within the HO2S 3 sensor.
- Wiring Issues: Damaged or corroded wiring connections leading to the sensor can also trigger this code.
- ECM Malfunction: A malfunctioning engine control module (ECM) can also cause issues with the heater control circuit.
- Sensor Failure: If the HO2S 3 sensor itself is faulty, it can lead to a low heater control circuit code.
Symptoms of P0043 Nissan
- Check Engine Light: The most common symptom associated with this code is the illumination of the check engine light on the vehicle's dashboard.
- Decreased Fuel Efficiency: A malfunctioning HO2S heater control circuit can lead to an incorrect fuel mixture, resulting in decreased fuel efficiency.
- Rough Idling: The engine may experience rough idling or hesitation when the HO2S 3 sensor is not functioning properly.
- Failed Emissions Test: The vehicle may fail an emissions test due to increased emissions output caused by inaccurate readings from the faulty sensor.
How to Fix P0043 Nissan
- Diagnostic Check: Begin by using a diagnostic scanner to retrieve the specific code and determine the exact cause of the issue.
- Check Wiring: Inspect the wiring connections leading to the HO2S 3 sensor for any signs of damage or corrosion and repair as necessary.
- Replace Heater Element: If the heater element within the sensor is faulty, it will need to be replaced.
- Replace Sensor: If the sensor itself is determined to be faulty, it will need to be replaced with a new one.
- Clear Codes: After completing the repair, clear the diagnostic trouble codes from the ECM and test drive the vehicle to ensure the issue has been resolved.
Cost to Fix P0043 Nissan
The typical repair costs for addressing a P0043 code on a Nissan vehicle can vary depending on the specific cause of the issue and the labor rates in your area. In general, replacing the HO2S 3 sensor heater control circuit can range from $150 to $300, including parts and labor. Additional costs may be incurred if other components need to be replaced or if there are wiring issues that require repair. It's important to note that diagnostic time and labor rates at auto repair shops can vary, so it's advisable to check with local providers for a more accurate estimate.
Tech Notes for P0043 Nissan
When is the Code Detected?
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Frequently Asked Questions about P0043 Nissan Code
No Frequently Asked Questions about P0043 Nissan Code found.
Discuss the causes and fixes for P0043 Nissan OBDII Code
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What part? sensor or the fuse? What model and year is your Nissan? every model have the sensor and fuse on different location.
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The P0043 code is for the "Oxygen Sensor 3". The"Oxygen Sensor 3" is the last O2 sensor in the exhaust system.
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Thanks for the pictures. I replaced the sensor and light came back on same code p0043. I checked with a test light for voltage at plug and also checked the one 02 sensor fuse I found under hood. All seemed to be ok.
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I replaced the sensor and light came back on same code p0043. I checked with a test light for voltage at plug and also checked the one 02 sensor fuse I found under hood. All seemed to be ok.
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Check if you have battery voltage at the Pin #2 of the connector. Use a volt meter an not a test light. If you do have battery voltage check the sensor as shown on the image below. If you do not have battery voltage, the the wire is damage between the sensor and Engine Control Module.
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how much voltage should I have at the wiring harness? regular battery voltage?
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I have 11.1 volts at the harness and have 4 ohms between 2,3 on the 02 sensor.
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Yes, whatever the battery voltage is.
If the sensor is OK and there is battery voltage at pin #2 (tested with sensor disconnected), then the next step is to check the wire from the sensor connector pin #3 (test with sensor disconnected) and the ECM. If the wire is OK, then the problem is the ECM. -
Only thing I can give you is that the wire is "Blue" and that is the "Pin #17" at the ECM connector.
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Ok so all checks out fine. During the test drive all I/m cleared and set to ok around 10 miles. Once I hit 13 miles the light came back on for p0043 again. I did monitor the drive and o2 sensors seemed to be working. cat temp reached 750 or so. Any further info would be great before I purchase a new ecm.
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Any exhaust leaks? If no leaks are present, then my best guess is that you have a bad sensor.
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Doesn't have any exhaust leaks and I did replace the sensor 3 first off. I also have tested it and it is good. is it possible for the p0043 code to be tripped from a different o2 sensor?
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I have a 2008 Nissan Rogue. What is the location of the B1S3 oxygen sensor? Is it upstream or downstream? Also is there a specific part number?
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Unfortunately, I don't have the part number. Here is the only image I got of the sensor location:
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