2024 Hyundai Tucson / Sonata EGR Valve Electrical Short TSB

Why This Matters

Hyundai has identified an issue with the Exhaust Gas Recirculation (EGR) valve assembly in certain 2024 Hyundai Tucson and Sonata vehicles. A sensor within the EGR valve may have been contaminated with solder flux during manufacturing, leading to an electrical short. This electrical short can cause the Malfunction Indicator Lamp (MIL) to illuminate, indicating a potential issue with the vehicle's emissions system or engine performance. Addressing this proactively ensures your vehicle operates correctly and avoids potential long-term issues.

Symptoms

Owners of affected 2024 Hyundai Tucson and Sonata vehicles may notice the "Malfunction Indicator lamp (MIL) illumination" on their dashboard. This warning light indicates a problem with the engine or emissions system. The underlying cause is an electrical short within the EGR valve assembly.

Fault Codes / DTCs

When the electrical short occurs in the EGR valve assembly, diagnostic trouble codes (DTCs) related to the EGR system may be stored in the vehicle's computer. The following DTCs are associated with this issue:

• P0405
• P0642
• P0652
• P0404
• P049D
• P240F

These codes specifically point to problems within the EGR circuit or performance, confirming the presence of the 2024 Hyundai Tucson EGR valve electrical short.

Diagnosis / Trigger Conditions

The root cause of the MIL illumination and associated DTCs is an electrical short within the EGR valve assembly. This short is attributed to solder flux contamination of a sensor during the manufacturing process. The issue affects 2024 Hyundai Tucson (NX4) models with the Theta 2.5 GDI engine produced between January 17, 2024, and February 22, 2024. It also impacts 2024 Hyundai Sonata (DN8) models with the Theta 2.5 GDI engine produced from February 6, 2024, to February 16, 2024, and 2024 Hyundai Sonata Hybrid (DN8 HEV) models with the Nu 2.0 GDI engine produced between February 6, 2024, and February 24, 2024.

Important Warnings and Information for Owners

Hyundai Service Campaign 9B3 (TSB 25-01-023H) includes several critical instructions for technicians, which also provide important information for vehicle owners:

• Dealer Action: Dealers are required to perform this service campaign on all affected vehicles before customer retail delivery and whenever an affected vehicle is brought in for any maintenance or repair.
• Part Replacement: If a part is found to need replacement during this campaign and is still under warranty, a separate claim should be submitted. For parts out of warranty, a Prior Approval request for goodwill consideration is necessary.
• EGR Control Valve Handling: Technicians are explicitly instructed: "Do NOT use if damaged" when handling the EGR control valve to prevent internal damage.
• EGR Cooler Gasket: The EGR cooler gasket must "Do NOT reuse the EGR cooler gasket." during the repair process.
• Coolant Mixing: For vehicles requiring coolant refill, technicians are advised: "do NOT use 100% full strength. Prepare coolant mixed with distilled/filtered water to refill the cooling system: 45-60% coolant, diluted with water."
• Superseded Bulletin: This TSB supersedes bulletin 24-01-080H, which previously included the Crank Position Sensor (CKPS) in the parts information.

Repair Procedure Summary

The repair outlined in Hyundai Service Campaign 9B3 (TSB 25-01-023H) involves replacing the EGR valve assembly and gasket. The procedure varies slightly between hybrid and non-hybrid models but generally includes:

1. Preparation: Recording customer radio presets and disconnecting the high-voltage circuit and/or the 12V positive connector from the auxiliary battery (for hybrids) or the negative battery terminal (for non-hybrids).
2. Disassembly (Hybrid Models): Removing the service interlock connector, loosening mounting clamps, and removing the air intake hose. Disconnecting the EGR control valve connector and removing the EGR valve cooler pipe mounting nuts.
3. Disassembly (Non-Hybrid Models): Removing the battery, battery tray, engine cover, air duct, and air cleaner assembly. Lifting the vehicle, removing the engine room undercover, draining coolant, and removing the heat protector, front muffler, water inlet pipe, and exhaust manifold.
4. EGR Valve Removal: Removing the mounting bolts and the EGR valve itself.
5. EGR Cooler Removal: For non-hybrid models, removing the EGR cooler and EGR cooler pipe.
6. Installation: Installing the new EGR valve assembly and gasket, ensuring proper torque specifications are met for all fasteners. The EGR pipe gasket must be mounted correctly, and the EGR control valve tightened to specification.
7. Reassembly: Reinstalling all components in the reverse order of removal. This includes carefully detaching and reattaching the plastic clip securing the Crankshaft Position Sensor (CKPS) wiring.
8. Coolant Refill: For non-hybrid models, refilling the engine with coolant using the Integrated Thermal Management (ITM) coolant filling method.
9. Digital Documentation: Taking required photos of the newly installed EGR valve and campaign sticker, along with VIN details and repair date, and uploading them.
10. Final Check: Starting the engine to confirm proper operation.

Required Parts and Tools

Technicians will require specific parts and materials for this repair, including:

• EGR Valve Assembly: Part numbers 28400-2J310QQH (Sonata Hybrid) or 28400-2S000QQH (Sonata/Tucson).
• Gaskets: Various EGR pipe gaskets (e.g., 28492-2J000QQH, 28493-2S040QQH, 28493-2S030QQH), exhaust pipe gaskets, catalyst case gaskets, thermostat housing gaskets, and O-rings.
• Coolant: Part number 00232-19098WAR (1 Quart). Note that coolant must be diluted to 45-60% strength with distilled/filtered water.
• Campaign Sticker: Part number NP001-SC9B3.
• Vehicle Emission Recall - Proof of Correction Card: Part number NP050-09006 (for specific states).

Owner Action

If you own a 2024 Hyundai Tucson (NX4) with a Theta 2.5 GDI engine, a 2024 Hyundai Sonata (DN8) with a Theta 2.5 GDI engine, or a 2024 Hyundai Sonata Hybrid (DN8 HEV) with a Nu 2.0 GDI engine, and your vehicle falls within the specified production dates, it is subject to Service Campaign 9B3 (TSB 25-01-023H). Hyundai is performing this repair free of charge. You should contact your authorized Hyundai dealer to schedule an appointment to have the EGR valve assembly and gasket replaced. The dealer can check your vehicle's eligibility using the "Vehicle Information" screen via WebDCS to identify open campaigns. Even if your MIL is not illuminated, it is crucial to have this campaign performed to prevent the 2024 Hyundai Tucson EGR valve electrical short from occurring.

NHTSA ID: 11015669