U0D39 - Communication Error in Electric Power Steering Systems for Honda and Acura Vehicles

Quick Answer

U0D39 means: U0D39 indicates a communication error in the electric power steering system.

Fix: Check and replace faulty components Cost: $400 - $800 Time: 90-180 minutes

Can I drive with U0D39? Immediate attention is advised to avoid steering difficulties and safety risks.

Common Questions

What does U0D39 mean and how does it affect my car?

The U0D39 code indicates a communication error in your car's electric power steering system. This could lead to steering difficulties, especially at low speeds, making your vehicle harder to control. It's crucial to address this issue promptly to ensure safe driving.

What are the most common causes of U0D39 and how much does it cost to fix?

Common causes include a faulty EPS control module, wiring issues, or software glitches. Repair costs can range from $100 to $800 depending on the necessary repairs, with wiring repairs being less expensive than module replacements.

Can I drive my car with U0D39 or should I stop immediately?

While you may be able to drive your vehicle short distances, it is not safe to ignore the U0D39 code. Loss of power steering assist can make steering difficult, especially in tight spaces or during emergencies, so it's best to have the issue diagnosed and repaired as soon as possible.

How can I diagnose U0D39 myself using GeekOBD APP?

Using the GeekOBD APP, perform a full OBD2 scan to retrieve the U0D39 code and any related codes. Check the freeze frame data for conditions when the code was set, and visually inspect the EPS wiring and connections for damage.

What vehicles are most commonly affected by U0D39?

The U0D39 code is commonly reported in 2015 to 2018 Honda Civic and Acura ILX models. If you own one of these vehicles, be aware of this potential issue as it has been noted in various repair reports.

How can I prevent U0D39 from happening again?

To prevent U0D39 from recurring, regularly inspect your vehicle's wiring and electrical connections for wear and corrosion, and ensure that software updates are performed during routine maintenance.

What is U0D39?

The diagnostic trouble code (DTC) U0D39 indicates a communication error within the electric power steering (EPS) system, primarily affecting certain Honda and Acura models manufactured from 2015 to 2018. This code signifies that the EPS control module is not communicating properly with other vehicle systems, such as the engine control module (ECM) or the body control module (BCM). Real-world implications of this issue can lead to a loss of power steering assist, making steering more difficult and potentially dangerous, especially at low speeds or during parking maneuvers. Drivers may notice that their steering feels unusually heavy or unresponsive, particularly if they are accustomed to the typical ease of steering in modern vehicles. Ignoring this code can lead to further complications, including increased wear on steering components and potential safety risks due to compromised steering response. It’s essential to address the U0D39 code promptly to ensure safe and reliable vehicle operation.

System: U - Network (Communication, CAN Bus)

Symptoms

Common symptoms when U0D39 is present:

  • Steering wheel feels unusually heavy or hard to turn, especially at low speeds or when parking.
  • Check engine light or EPS warning light illuminated on the dashboard, indicating a fault in the steering system.
  • Unresponsive steering assist when making turns, leading to increased effort required from the driver.
  • Intermittent loss of power steering assist, where the steering may work correctly at times and fail at others.
  • Unusual noises from the steering column, such as grinding or whining, when turning the wheel.

Possible Causes

Most common causes of U0D39 (ordered by frequency):

  1. The most common cause of the U0D39 code is a faulty EPS control module, with a likelihood of about 40%. This module may fail due to electrical issues or internal components wearing out over time.
  2. Another common cause is a wiring issue, such as damaged or corroded wiring harness connections, accounting for approximately 30% of cases. These problems can disrupt communication between the EPS and other critical vehicle systems.
  3. A third potential cause involves software glitches in the EPS system. Regular software updates can prevent these problems, so ensuring your vehicle’s software is up-to-date is essential.
  4. Less common but serious causes may include a failure in the power steering pump, which can lead to complete loss of steering assist.
  5. A rare cause could be an internal failure of the steering rack, which may require replacement if identified during diagnostics.

U0D39 Repair Costs

Cost Breakdown by Repair Type

EPS Control Module Replacement

Replacing the faulty EPS control module may resolve the U0D39 code and restore proper steering functionality.

  • Total: $400 - $800
  • Success rate: 85%
Wiring Repair

Repairing or replacing damaged wiring and connectors in the EPS system.

  • Total: $100 - $300
  • Success rate: 70%
Money-Saving Tips for U0D39
  • Start with the most common and least expensive repairs first
  • Use GeekOBD APP to confirm diagnosis before replacing expensive parts
  • Consider preventive maintenance to avoid future occurrences
  • Compare prices for OEM vs aftermarket parts based on your needs
  • Address the issue promptly to prevent more expensive secondary damage

Diagnostic Steps

Professional U0D39 Diagnosis Process

Follow these systematic steps to accurately diagnose U0D39. Each step builds on the previous one to ensure accurate diagnosis.

Step 1: Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion in the EPS system (5-10 minutes)

Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion in the EPS system (5-10 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 2: Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context, including any related codes (10-15 minutes)

Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context, including any related codes (10-15 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 3: Step 3: Component testing - Use a multimeter to test the EPS control module and wiring harness for continuity and voltage (20-30 minutes)

Step 3: Component testing - Use a multimeter to test the EPS control module and wiring harness for continuity and voltage (20-30 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 4: Step 4: System function test - Verify the proper operation of the EPS system after any repairs and clear the codes using the GeekOBD APP (10-15 minutes)

Step 4: System function test - Verify the proper operation of the EPS system after any repairs and clear the codes using the GeekOBD APP (10-15 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 5: Step 5: Road test verification - Drive the vehicle under various conditions to confirm the success of the repairs and ensure the steering operates smoothly (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to confirm the success of the repairs and ensure the steering operates smoothly (15-20 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.

Important Notes

  • Always verify the repair with GeekOBD APP after completing diagnostic steps
  • Clear codes and test drive to ensure the problem is resolved
  • Address underlying causes to prevent code recurrence

Real Repair Case Studies

Case Study 1: Honda Civic Power Steering Malfunction

Vehicle: 2017 Honda Civic, 45,000 miles

Problem: Customer reported heavy steering and EPS warning light on the dashboard.

Diagnosis: Performed OBD2 scan and retrieved U0D39 code. Visual inspection found corroded wiring in the EPS harness.

Solution: Replaced the damaged wiring and cleared the codes. Verified steering assist was restored.

Cost: $250 for wiring repair.

Result: Customer reported no further issues and was satisfied with the repair.

Case Study 2: Acura ILX EPS Control Module Replacement

Vehicle: 2016 Acura ILX, 60,000 miles

Problem: Customer complained of intermittent loss of power steering assist.

Diagnosis: Scanned for codes and confirmed U0D39. Testing of the EPS control module revealed failure.

Solution: Replaced the EPS control module and updated the vehicle’s software.

Cost: $600 for parts and labor.

Result: Repair resolved the steering issues, and customer expressed satisfaction with the quick turnaround.

Diagnose U0D39

Use GeekOBD APP for professional diagnosis!

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Code Information

Code: U0D39
System: Network (Communication, CAN Bus)
Severity: HIGH
Category: Network Codes