P0057 on 2006-2010 Hyundai Sonata 3.3L V6: Causes, Fixes, and O2 Sensor Guide

What's Unique About the 2006-2010 Hyundai Sonata

The 2006-2010 Hyundai Sonata with the 3.3L V6 uses four oxygen sensors. 🎬 Watch: See the locations of all four O2 sensors. For this specific P0057 code, the issue is with the 'downstream front' sensor. Interestingly, on this engine, three of the four O2 sensors (including this one) are often the same part number, with only the downstream rear sensor having a longer wire. The confirmed OEM part number for Bank 2, Sensor 2 is 39210-3C200. This part is also used on the Azera, Sedona, and Sorento. The Bank 2 Sensor 2 is relatively easy to access from underneath the car, making replacement a common DIY task.

Symptoms You May Notice

• Check Engine Light is on
• Reduced fuel economy
• Failure to pass an emissions inspection
• Black smoke from the exhaust or a rough idle may occur in some cases, but this is less common.

Most Likely Causes

1. Failed Bank 2, Sensor 2 Oxygen Sensor 🔴 High Probability → Shop Oxygen Sensor The internal heater element within the O2 sensor is a common failure point due to thermal cycling and age, especially on vehicles with over 80,000 miles. It's a standard wear-and-tear component.
   How to confirm: Disconnect the sensor and measure the resistance between the two heater circuit pins (usually the two same-colored wires) with a multimeter. 🎬 Watch: How to test oxygen sensor heater circuits. A reading of 'OL' (Open Line) or a value far from the specification indicates a failed heater. A good sensor should have a resistance of approximately 8.1 to 11.1 ohms at 21°C (70°F).
   Typical fix: Replace the Bank 2, Sensor 2 oxygen sensor. The OEM part is Hyundai P/N 39210-3C200.
   Est. part cost: $40-$90
2. Damaged Wiring or Corroded Connector 🟡 Medium Probability The sensor and its wiring are located under the vehicle, exposed to road debris, moisture, and exhaust heat, which can cause wires to fray, melt, or break over time. The connector pins can also corrode.
   How to confirm: Visually inspect the wiring harness leading to the B2S2 sensor for any signs of damage, melting, or corrosion. Check that the connector is securely plugged in and the pins are clean and free of corrosion. Test the control wire (from harness connector terminal 2 to PCM terminal 73) for continuity; resistance should be less than 2 ohms.
   Typical fix: Repair the damaged section of the wiring harness or clean/replace the connector.
   Est. part cost: $5-$30
3. Blown Fuse ⚪ Low Probability A short circuit in the heater circuit (either in the wiring or the sensor itself) can cause the dedicated O2 sensor heater fuse to blow.
   How to confirm: Locate the fuse box in the engine compartment. Check the 15A fuse labeled 'SNSR 1' (or sometimes 'SENSOR 1'). Visually inspect if the fuse is blown or test for continuity with a multimeter.
   Typical fix: Replace the blown fuse with one of the same amperage. If it blows again immediately, a short circuit is present in the wiring or the sensor that must be found and fixed.
   Est. part cost: $1-$5

Rare But Worth Checking

• Faulty Powertrain Control Module (PCM): → Shop Engine Control Module (ECM) This is extremely rare. The PCM's internal driver for the heater circuit can fail. This should only be considered after all other possibilities (sensor, wiring, fuse) have been exhaustively ruled out by following the service manual diagnostic procedure.

Diagnosis Steps

1. Verify the code with an OBD-II scanner.
2. Locate the fuse box in the engine compartment and check the 15A fuse labeled 'SNSR 1'. Replace if blown.
3. Safely raise the vehicle and locate the Bank 2, Sensor 2 oxygen sensor. It is on the exhaust manifold closer to the radiator, after the catalytic converter.
4. Inspect the wiring harness and connector leading to the sensor for any obvious signs of damage, melting, or corrosion.
5. If the wiring and fuse are good, disconnect the sensor. Use a multimeter to test the resistance of the heater circuit within the sensor itself. A good sensor should read between 8.1 and 11.1 ohms at room temperature. If the resistance is infinite (open circuit) or zero (shorted), the sensor has failed and must be replaced.
6. If the sensor's resistance is within spec, check for power at the harness connector. With the key on, engine off, measure voltage between terminal 1 of the harness connector and chassis ground. It should be approximately battery voltage (12V). If power is missing, there is an open in the power circuit from the main relay/fuse box.
7. If power is present, check the control circuit for a short to ground. With the key off and sensor disconnected, measure resistance between terminal 2 of the harness connector and chassis ground. The resistance should be infinite (OL). If there is continuity, there is a short in the wire leading back to the PCM (Terminal 73).

Parts You'll Likely Need

• Oxygen Sensor (Bank 2, Sensor 2) (OEM #39210-3C200) — This is the most common cause of P0057, as the internal heater element fails over time. On this vehicle, it is the downstream sensor on the front (radiator side) catalytic converter.
  Trusted brands: Denso, NGK/NTK, Bosch, Walker
  OEM price range: $100-$160
  Aftermarket price range: $40-$90

Platform-Specific Known Issues

• A user on hyundai-forums.com with a 2007 Sonata reported this exact code. The community advised verifying the correct sensor location (Bank 2 = front/radiator side) and warned that simply replacing the sensor might not fix it if the control circuit itself is the problem, emphasizing the need for electrical testing.

Mechanic-Grade Diagnostic Values

• O2 Sensor Heater Element Resistance — expected: 8.1 - 11.1 Ω at 21°C (70°F). Failure: A reading of 'OL' (open circuit) or near zero (short circuit).
• Heater Power Supply Voltage at Harness — expected: Battery Voltage (approx. 12V) with Key On, Engine Off. Failure: Voltage significantly below 12V indicates an open or high resistance in the power feed circuit from the main relay/fuse box.
• Heater Control Circuit Wire Resistance — expected: < 2.0 Ω. Failure: Resistance higher than 2.0 Ω indicates a break or corrosion in the wire between the sensor connector (Terminal 2) and the PCM connector (Terminal 73).
• DTC Set Condition (Time) — expected: N/A. Failure: The PCM will store DTC P0057 if it detects the heater output voltage is lower than the threshold for more than 5 seconds.

Scan Tool Commands That Help

• Hyundai GDS (Global Diagnostic System) or equivalent advanced scanner: Live Data Monitoring: 'HO2S Heater(B2/S2)' — After starting the engine, a technician can monitor the heater duty cycle percentage commanded by the PCM. If the PCM is commanding the heater on (duty cycle > 0%) but voltage on the circuit remains low and the sensor doesn't warm up, it helps confirm the fault is in the circuit or sensor, not the PCM's logic.

Wiring & Ground Locations

• PCM Connector Terminal 73 — At the main Powertrain Control Module (PCM) harness connector.. This is the specific pin for the heater control circuit for Bank 2, Sensor 2. It is used for continuity testing the control wire back from the O2 sensor harness connector (Terminal 2).
• HO2S (B2/S2) Harness Connector — The 4-pin connector that plugs directly into the Bank 2, Sensor 2 oxygen sensor.. Terminal 1 is the 12V power feed from the main relay, and Terminal 2 is the control circuit ground provided by the PCM. All electrical tests start here.

Real Owner Repair Stories

• Hyundai Forums user (2007 Hyundai Sonata 3.3L, 150k miles) — P0057 code appeared immediately after replacing the exhaust middle pipe (with flex pipes).
  ❌ Tried (didn't work) Replacing the Bank 2 Sensor 2 oxygen sensor., Swapping the PCM with a known-good unit from a 2006 Sonata.
  ✅ What actually fixed it The user did not post the final resolution, but after replacing the sensor and confirming the PCM was good, the only remaining likely cause was damage to the wiring harness. The user noted the old exhaust pipe dropped before the O2 sensor was disconnected, which strongly suggests the wiring was stretched, broken, or shorted during the previous repair. The fix would be to find and repair the damaged section of the harness between the sensor connector and the PCM.

Model Year Variations Within This Range

• 2009-2010: The NF Sonata received a mid-cycle refresh. For the 3.3L V6, this included an increase in horsepower from 235 hp to 249 hp. This change did not affect the O2 sensor part numbers or the diagnostic procedure for P0057.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• Subframe Corrosion 🔴 High — Very common in 'Salt Belt' regions, leading to a recall (Campaign 113) and a class-action lawsuit. Can cause suspension component failure. (Ref: Recall 113 / NHTSA Campaign 13V354000)
• Leaking Valve Cover Gaskets 🟠 Medium — A very common issue for the 3.3L V6. The front (Bank 2) gasket can leak oil directly onto the alternator, causing premature alternator failure. The rear is also common but less consequential.
• Timing Chain Tensioner Wear 🟠 Medium — The 3.3L Lambda V6 can develop a rattle on cold startup, indicating a worn timing chain tensioner that is losing oil pressure. If left unaddressed, it can lead to more significant timing system problems.
• Failing Sun Visors 🟡 Low — Extremely common. The internal mechanism fails, causing the visor to droop and not stay in the stowed position.
• Output Speed Sensor Failure 🟠 Medium — Can cause harsh shifting, getting stuck in one gear (limp mode), and a P0722 trouble code. It is a common failure on the transmission.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A used part is generally NOT recommended for the oxygen sensor itself, as it is a wear item. However, sourcing a used wiring harness 'pigtail' from a junkyard is a smart choice if your vehicle's connector is melted, corroded, or damaged.

Donor-vehicle mileage cap: roughly under 80000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• For a wiring pigtail: Ensure the connector is not cracked or melted.
• Check that the locking tab clicks securely.
• Inspect for clean, corrosion-free pins.
• Ensure at least 6-8 inches of wire is attached for easier splicing.

OEM-only on this vehicle (don't cheap out):

• Powertrain Control Module (PCM) - Must be OEM and may require programming to the vehicle's VIN.

Aftermarket brands forum-validated for this vehicle:

• Denso
• NGK / NTK

Brands owners have reported issues with on this vehicle:

• Unbranded, 'white-box' sensors from online marketplaces. Forum users frequently report premature failure and incorrect readings from cheap, no-name sensors, leading to recurring codes.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0037 — This is the equivalent heater circuit low code for the opposite bank (Bank 1, Sensor 2). Seeing both codes together could suggest a common problem like a blown 'SNSR 1' fuse or widespread wiring damage.
• P0051 — Indicates a heater circuit low fault for the upstream sensor on the same bank (Bank 2, Sensor 1). If the 'SNSR 1' fuse is blown, it may cause codes for multiple O2 sensor heaters that share the circuit.
• P0058 — This is the 'Heater Control Circuit High' code for the same sensor (Bank 2, Sensor 2). It indicates the opposite problem—a short to power—but points to a fault within the same sensor or wiring harness.
• P0562 — System Voltage Low. This can be a consequence of a failing alternator, which is a very common issue on this vehicle caused by the Bank 2 valve cover gasket leaking oil. Unstable system voltage can cause faults in various electronic modules and sensors, including the O2 heater circuits.

Frequently Asked Questions