2021 Hyundai MDPS Steering System Repair TSB

Hyundai has issued Technical Service Bulletin (TSB) 20-ST-001H-2, dated September 2020, to provide comprehensive repair information for the column-mounted Motor Driven Power Steering (MDPS) system. This bulletin updates and supersedes the previous TSB 20-ST-001H-1, specifically revising causal part numbers in the warranty information table and updating the bearing noise example video. The primary purpose of this TSB is to guide technicians in replacing individual components of the MDPS system rather than the entire assembly.

This TSB is applicable to a wide range of Hyundai models, including the Accent (RB/HC), Azera (HG), Elantra (MD/UD/AD), Elantra Coupe (JK), Elantra GT (GD/PD), Ioniq Hybrid/Plug-In/Electric Vehicle (AE HEV/AE PHEV/AE EV), Kona (OS), Kona EV (OS EV), Palisade (LX2), Santa Fe (TMA), Santa Fe/XL (NC), Santa Fe Sport (AN), Sonata (YF/LF/DN8a), Sonata Hybrid/Plug-In (YF HEV/ LF HEV/LF PHEV/DN8 HEV), Tucson (LM/TL), Tucson Fuel Cell (LM FCEV), and Veloster (FS/JS). Owners of these vehicles who experience power steering problems, such as warning lights, unusual noises, or a noticeable change in steering feel, should be aware of the detailed diagnostic and repair procedures outlined in this document. This Hyundai Tucson MDPS repair guide will help you understand the common problems and solutions.

What's Being Addressed

The column-mounted Motor Driven Power Steering (C-MDPS) system consists of several key components that can be replaced individually. These include the Column & Shaft Assembly, Column & Housing Assembly, C-MDPS Motor, C-MDPS ECU, Universal Joint Assembly, Electric Power Pack (which combines the C-MDPS Motor and C-MDPS ECU assembly), Worm Shaft Assembly, and Steering Universal Joint Pinch Bolts. The Electric Power Pack is specifically applicable to Palisade (LX2) and Santa Fe (TMa) models.

Symptoms

Owners may encounter several distinct symptoms indicating a malfunction within the MDPS system. These can manifest as a "warning lamp illuminated" on the instrument cluster, a "CAN Line Error," or a general "binding/sticking steering feel" that makes turning the wheel difficult or inconsistent. Specific noises are also common indicators of MDPS system problems.

Common noise-related symptoms include:

• Small bearing noise: This is often described as a "growling/grinding/bearing noise" and typically originates from the worm gear area of the steering column. If confirmed, the worm gear assembly should be replaced, referring to TSB 20-ST-002H-2 or 20-ST-003H-1.
• Ticking noise: If you hear a "ticking noise," it usually points to an issue within the column and housing assembly. If confirmed, the column and housing assembly should be replaced.
• Motor noise: Any unusual sounds coming directly from the C-MDPS motor itself suggest a problem with that specific component. If confirmed, the C-MDPS motor or C-MDPS Electric Power Pack should be replaced.

Fault Codes / DTCs

When the MDPS warning lamp illuminates, Diagnostic Trouble Codes (DTCs) are typically stored in the vehicle's computer system. TSB 20-ST-001H-2 provides an extensive list of DTCs related to the C-MDPS system, detailing their descriptions, initial inspection methods, and recommended repair actions. It's important to note that some MDPS-related DTCs may also appear in other systems, such as the Brake/ABS/ESC system, requiring a comprehensive check of all relevant systems. For vehicles that display 7-digit DTCs, technicians should focus on matching the first 5 digits to the codes listed below.

| DTC | Description | First Inspection Method | Repair Recommendations | | :---- | :---------------------------------- | 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(This is a continuation of the previous thought process, focusing on expanding the contentMarkdown based on the detailed PDF analysis.)

Expanding the contentMarkdown:

Initial Introduction: (Already good, but can add more detail about the MDPS system components being addressed.)

New Section: What's Being Addressed

• List the key components of the C-MDPS system mentioned on page 2: Column & Shaft Assembly, Column & Housing Assembly, C-MDPS Motor, C-MDPS ECU, Universal Joint Assembly, Electric Power Pack, Worm Shaft Assembly, Steering Universal Joint Pinch Bolts. Mention the Electric Power Pack's specific applicability to Palisade (LX2) and Santa Fe (TMa).

Symptoms: (Expand with more detail from page 6 and 12-13)

• Reiterate