P0143 Infiniti Code - Heated Oxygen Sensor 3 Heater Control Circuit High
Quick Answer
The rear heated oxygen sensor (or sensor 3 for some vehicles), after three way catalyst (manifold), monitors the oxygen level in the exhaust gas on each bank. Common causes include Faulty Heated Oxygen Sensor Bank 1 Sensor 3, Heated Oxygen Sensor Bank 1 Sensor 3 harness is open or shorted, Heated Oxygen Sensor Bank 1 Sensor 3 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
- P0143 Infiniti indicates Heated Oxygen Sensor 3 Heater Control Circuit High.
- Common causes
- Common causes include Faulty Heated Oxygen Sensor Bank 1 Sensor 3, Heated Oxygen Sensor Bank 1 Sensor 3 harness is open or shorted, Heated Oxygen Sensor Bank 1 Sensor 3 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 P0143 Infiniti Description
This sensor is made of ceramic zirconia. The zirconia generates voltage from approximately 1V in richer conditions to 0V in leaner conditions. Under normal conditions the heated oxygen sensor 3 is not used for engine control operation.
What are the Possible Causes of the DTC P0143 Infiniti?
- Faulty Heated Oxygen Sensor Bank 1 Sensor 3
- Heated Oxygen Sensor Bank 1 Sensor 3 harness is open or shorted
- Heated Oxygen Sensor Bank 1 Sensor 3 circuit poor electrical connection
How to Fix the DTC P0143 Infiniti?
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.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0143 Infiniti 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 P0143 Infiniti Code
1. What does the OBDII code P0143 mean for an Infiniti?
P0143 indicates a problem with the Heated Oxygen Sensor 3 Heater Control Circuit, specifically that the circuit is registering a high voltage.
2. What are the symptoms of code P0143 in an Infiniti?
Common symptoms include an illuminated check engine light, poor fuel efficiency, rough idling, and potentially increased vehicle emissions.
3. What causes the P0143 code on an Infiniti?
Potential causes include a faulty oxygen sensor, damaged wiring or connectors, a blown fuse, or issues with the vehicle’s powertrain control module (PCM).
4. How do I diagnose the P0143 code on my Infiniti?
Start by inspecting the wiring and connectors for damage, test the oxygen sensor heater circuit with a multimeter, and check for blown fuses or PCM issues.
5. Can I drive my Infiniti with a P0143 code?
While the vehicle may still be drivable, it’s not recommended as it can lead to reduced performance, poor fuel efficiency, and potential damage to the catalytic converter over time.
6. How is the P0143 code fixed?
Repairs may include replacing the faulty oxygen sensor, repairing damaged wiring or connectors, or addressing issues in the PCM or fuse box.
7. How much does it cost to fix the P0143 code on an Infiniti?
The cost varies but replacing an oxygen sensor typically ranges from $150 to $400, depending on the vehicle model and labor rates.
8. Can a bad oxygen sensor cause the P0143 code?
Yes, a faulty oxygen sensor is one of the most common causes of the P0143 code.
9. How do I prevent the P0143 code from occurring again?
Regular maintenance, periodic inspection of the oxygen sensor and wiring, and addressing check engine light issues promptly can help prevent recurrence.
10. Will clearing the code with a scanner fix the P0143 issue?
Clearing the code might temporarily turn off the check engine light, but the underlying issue must be repaired to prevent the code from returning.
Discuss the causes and fixes for P0143 Infiniti OBDII Code
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