C0338 - Unusual Steering Wheel Position Sensor Malfunction in Common Vehicles like Chevrolet and GMC

Quick Answer

C0338 means: C0338 indicates a malfunction with the steering wheel position sensor, affecting vehicle stability and handling.

Fix: Check and replace faulty components Cost: $150 - $300 Time: 90-180 minutes

Can I drive with C0338? Immediate attention is advised to avoid safety hazards while driving.

Common Questions

What does C0338 mean and how does it affect my car?

The C0338 code indicates a malfunctioning steering wheel position sensor. This can lead to poor handling, increased wear on steering components, and potential safety risks. It's essential to address this issue promptly to ensure safe vehicle operation.

What are the most common causes of C0338 and how much does it cost to fix?

Common causes include a faulty steering wheel position sensor, wiring issues, and ECU problems. Repair costs can range from $100 for wiring repairs to $300 for sensor replacement.

Can I drive my car with C0338 or should I stop immediately?

While it may be possible to drive your vehicle short distances, it is not recommended due to safety concerns. The steering behavior may be unpredictable, and it's best to have the issue diagnosed and repaired as soon as possible.

How can I diagnose C0338 myself using GeekOBD APP?

Start by connecting the GeekOBD APP to your vehicle's OBD2 port. Retrieve the DTC codes and examine the freeze frame data for context. Follow the diagnostic steps to check the sensor and wiring.

What vehicles are most commonly affected by C0338?

The C0338 code is frequently seen in 2014-2018 Chevrolet Silverado and GMC Sierra models. It's advisable to check for any recalls or technical service bulletins related to this issue.

How can I prevent C0338 from happening again?

Regular vehicle maintenance, including inspections of the wiring and connectors, can help prevent issues. Keeping electrical connections clean and dry is crucial for sensor longevity.

What is C0338?

The DTC C0338 code indicates a problem with the steering wheel position sensor, which is crucial for various vehicle systems such as stability control and advanced driver assistance features. This code can trigger when the sensor's signal is out of range or when there is an issue with the wiring or connectors associated with the sensor. In practical terms, this means that your vehicle may experience issues like improper steering feel, compromised stability control, and even the activation of the check engine light. Drivers often notice that their vehicle's steering feels off, leading to concerns about safety and drivability. This issue is notably reported in various models from General Motors, especially the Chevrolet Silverado (2014-2018) and GMC Sierra (2014-2018), where a malfunctioning steering wheel position sensor can lead to unexpected handling characteristics. Ignoring this code can lead to further complications, such as increased wear on steering components and potential safety risks while driving under adverse conditions. Addressing the DTC C0338 promptly is essential to ensure your vehicle operates safely and efficiently.

System: C - Chassis (ABS, Steering, Suspension)

Symptoms

Common symptoms when C0338 is present:

  • The check engine light illuminates on the dashboard, signaling that there's a fault that needs immediate attention.
  • Drivers may experience a lack of responsiveness or unusual resistance when turning the steering wheel, indicating a problem with the steering system.
  • Fuel economy may decrease due to the vehicle's stability systems working harder to compensate for the steering sensor malfunction, potentially reducing efficiency by 5-10%.
  • Inconsistent steering feel, where the steering may feel loose or overly tight, impacting the overall driving experience.
  • Activation of stability control or traction control systems may occur unexpectedly, causing the vehicle to behave unpredictably in certain driving conditions.

Possible Causes

Most common causes of C0338 (ordered by frequency):

  1. {'cause': 'Faulty steering wheel position sensor - 60% likelihood, often due to wear or manufacturing defects.', 'details': 'The sensor can fail due to prolonged exposure to moisture or heat, which affects its performance.'}
  2. {'cause': 'Wiring issues or poor connections - 25% likelihood, typically due to fraying or corrosion over time.', 'details': 'Inspect wiring harnesses for signs of damage, which can disrupt the signal sent to the ECU.'}
  3. {'cause': 'ECU (Engine Control Unit) malfunction - 10% likelihood, where the ECU fails to interpret the signals correctly.', 'prevention': 'Regularly update vehicle software and perform diagnostics to catch ECU issues early.'}
  4. {'cause': 'Mechanical obstruction in the steering column - 3% likelihood, which can hinder sensor function.', 'details': 'Physical blockages may occur from debris or internal wear, impacting steering responsiveness.'}
  5. {'cause': 'Defective steering rack - 2% likelihood, which could affect overall steering performance.', 'details': 'Issues in the steering rack can lead to misalignment and incorrect sensor readings.'}

C0338 Repair Costs

Cost Breakdown by Repair Type

Steering Wheel Position Sensor Replacement

Replacing the faulty steering wheel position sensor with a new one to restore proper function.

  • Total: $150 - $300
  • Success rate: 90%
Wiring Repair

Repairing damaged wiring or connectors that may be affecting the sensor signal.

  • Total: $100 - $200
  • Success rate: 85%
ECU Reprogramming

Reprogramming the ECU if it is not properly recognizing the sensor readings.

  • Total: $80 - $150
  • Success rate: 70%
Money-Saving Tips for C0338
  • 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 C0338 Diagnosis Process

Follow these systematic steps to accurately diagnose C0338. 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 at the sensor and connector (5-10 minutes)

Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion at the sensor and connector (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 and confirm the C0338 code (10-15 minutes)

Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context and confirm the C0338 code (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 steering wheel position sensor for correct voltage and resistance readings (20-30 minutes)

Step 3: Component testing - Use a multimeter to test the steering wheel position sensor for correct voltage and resistance readings (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 proper operation of the steering system after repairs and clear codes with the GeekOBD APP (10-15 minutes)

Step 4: System function test - Verify proper operation of the steering system after repairs and clear codes with 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 ensure normal steering function and confirm repair success (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to ensure normal steering function and confirm repair success (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: Steering Wheel Position Sensor Replacement in 2016 Chevrolet Silverado

Vehicle: 2016 Chevrolet Silverado 1500, 75,000 miles

Problem: Customer reported a persistent check engine light and steering wheel felt loose.

Diagnosis: Diagnostic scan revealed DTC C0338. Visual inspection indicated a faulty steering sensor.

Solution: Replaced the steering wheel position sensor and performed a system function test.

Cost: $250 (sensor $150, labor $100)

Result: Issue resolved, and the steering performance returned to normal.

Case Study 2: Wiring Issue Diagnosis in 2017 GMC Sierra

Vehicle: 2017 GMC Sierra 1500, 60,000 miles

Problem: Customer experienced unusual steering behavior and stability control warnings.

Diagnosis: DTC scan confirmed C0338. Found damaged wiring in the steering column.

Solution: Repaired the wiring and verified sensor functionality.

Cost: $150 (wiring repair and labor)

Result: The customer reported improved steering feel and no further warning lights.

Diagnose C0338

Use GeekOBD APP for professional diagnosis!

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  • Step-by-step repair guidance
  • Professional-grade analysis
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Code Information

Code: C0338
System: Chassis (ABS, Steering, Suspension)
Severity: HIGH
Category: Chassis Codes