P0142 Code - O2 Sensor Circuit Malfunction Bank 1 Sensor 3
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
- P0142 indicates O2 Sensor Circuit Malfunction Bank 1 Sensor 3.
- 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 P0142 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 P0142?
- 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 P0142?
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 P0142 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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Information for Specific Makes
- P0142 Mercedes-Benz — O2 Sensor Circuit Malfunction Bank 1 Sensor 3
- P0142 Toyota — HO2S13 Circuit Fault
- P0142 Volkswagen — O2 Sensor Circuit Malfunction Bank 1 Sensor 3
Frequently Asked Questions about P0142 Code
1. What are the common symptoms of OBDII code P0142?
- Common symptoms of P0142 include poor fuel economy, rough idling, engine misfires, and a noticeable decrease in engine performance.
2. What does the OBDII code P0142 indicate?
- P0142 indicates an O2 sensor circuit malfunction in Bank 1 Sensor 3, meaning there is a problem with the signal from the downstream oxygen sensor in bank 1 of the engine.
3. What are the possible causes of O2 sensor circuit malfunction Bank 1 Sensor 3 (P0142)?
- Possible causes of P0142 include a faulty oxygen sensor, damaged wiring or connectors, exhaust leaks, or issues with the engine control module (ECM).
4. How can I diagnose the O2 sensor circuit malfunction in Bank 1 Sensor 3?
- Diagnosing P0142 involves using an OBDII scanner to read the code, inspecting the oxygen sensor and related wiring for damage, and testing the sensor's voltage output.
5. Can I drive my vehicle with the OBDII code P0142?
- It is not recommended to drive with P0142 as it can lead to decreased fuel efficiency, engine performance issues, and potential damage to other components over time.
6. How do I repair OBDII code P0142?
- Repairing P0142 may involve replacing the faulty oxygen sensor, repairing damaged wiring or connectors, fixing any exhaust leaks, and clearing the code with an OBDII scanner.
7. Is it possible to reset the O2 sensor circuit malfunction Bank 1 Sensor 3 code without fixing the issue?
- While you can temporarily clear the code by resetting the ECM, it is important to address the underlying problem causing P0142 to prevent further issues.
8. Can a dirty or contaminated oxygen sensor cause OBDII code P0142?
- Yes, a dirty or contaminated oxygen sensor can cause incorrect readings and lead to P0142. Cleaning or replacing the sensor may resolve the issue.
9. How long does it take to repair the O2 sensor circuit malfunction Bank 1 Sensor 3?
- The time to repair P0142 varies depending on the exact cause and extent of the issue. It could take anywhere from 30 minutes to a few hours to complete the repair.
10. Will OBDII code P0142 cause my vehicle to fail an emissions test?
- Yes, P0142 can cause your vehicle to fail an emissions test due to the malfunctioning O2 sensor affecting the emission control system. Repairing the issue is necessary for passing the test.
Discuss the causes and fixes for P0142 OBDII Code
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What exactly is your problem and what make, model and year is your vehicle?
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I had a P0142 code on a 2002 ford explorer, I cleaned the MAF and disconnected the battery to turn off the "service engine" light. When I had it smogged in california it failed the test because of the code and was printed on the paperwork so now I have to get it tested again. My question is do I need to buy a meter to delete the OBD code from the onboard computer before having it tested again or does it delete itself by disconnecting the battery and turning off the check engine light? The retest is free but if it fails again I have to pay another $59 to get it tested again PLUS $50 for a meter to delete the code. Anyone know?
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You can disconnect the car battery to reset the code, but you have to drive you vehicle again for a few days before getting the smog test done.
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