C0387 - Understanding DTC C0387: Common Issues in Chevrolet and GMC Vehicles

Quick Answer

C0387 means: DTC C0387 indicates a malfunction with the steering angle sensor.

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

Can I drive with C0387? Immediate attention is recommended to prevent safety hazards.

Common Questions

What does C0387 mean and how does it affect my car?

DTC C0387 signifies a malfunction in your vehicle's steering angle sensor, which is crucial for stability and control. If this sensor fails, it can lead to unpredictable steering behavior, impacting your driving experience and potentially compromising safety.

What are the most common causes of C0387 and how much does it cost to fix?

The most common causes include a faulty steering angle sensor, damaged wiring, or calibration issues. Repair costs can range from $100 for wiring repairs to $1500 for ECU replacements, depending on the specific problem identified.

Can I drive my car with C0387 or should I stop immediately?

While you might be able to drive short distances, it's not recommended. The steering issues caused by this code can lead to unsafe driving conditions, so it's best to have the problem diagnosed and repaired as soon as possible.

How can I diagnose C0387 myself using GeekOBD APP?

With the GeekOBD APP, you can perform a quick OBD2 scan to retrieve DTC C0387 and examine freeze frame data. This will help you understand the context of the fault, and you can use the app to monitor live data from the steering angle sensor during a test drive.

What vehicles are most commonly affected by C0387?

DTC C0387 is frequently seen in 2014-2019 Chevrolet Silverado and GMC Sierra models, among others. If you own these vehicles, being vigilant about steering-related issues is essential.

How can I prevent C0387 from happening again?

Regular maintenance, including inspections of the steering system, keeping an eye on wiring integrity, and ensuring proper alignment after repairs, can help prevent the occurrence of DTC C0387.

What is C0387?

DTC C0387 is a diagnostic trouble code that indicates a problem with the steering angle sensor, specifically within vehicles manufactured by General Motors, including popular models like the Chevrolet Silverado from 2014 to 2019 and GMC Sierra from 2014 to 2019. This code typically signals that there is a discrepancy in the data being sent from the steering angle sensor to the vehicle's electronic control module (ECM). The steering angle sensor is crucial for various systems, including electronic stability control (ESC) and traction control. When this sensor malfunctions, it can lead to poor vehicle handling, reduced stability, and increased wear on components. Drivers may experience symptoms such as a constant check engine light, erratic steering behavior, or difficulty in maneuvering the vehicle. Ignoring this code can lead to further complications, including a complete loss of steering control in extreme cases. For the safety of both the driver and passengers, it is essential to address this issue promptly.

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

Symptoms

Common symptoms when C0387 is present:

  • The check engine light is illuminated and remains on, indicating a need for diagnostic checks.
  • Steering may feel unresponsive or overly sensitive, leading to difficulty in controlling the vehicle, particularly during sharp turns.
  • You might notice a significant decrease in fuel efficiency, potentially around 10-15%, due to the vehicle's inability to optimize traction control.
  • The vehicle may exhibit warning messages on the dashboard related to stability control or traction control.
  • In severe cases, the steering wheel may not return to the center after a turn, leading to an unsafe driving condition.

Possible Causes

Most common causes of C0387 (ordered by frequency):

  1. The most common cause of DTC C0387 is a faulty steering angle sensor, which is responsible for relaying steering position data. This failure occurs in about 60% of cases.
  2. Another potential cause could be damaged wiring or connections related to the steering angle sensor, which may lead to intermittent issues that trigger the code.
  3. In some instances, calibration issues arise when the steering angle sensor has not been properly aligned after installation or maintenance, leading to erroneous readings.
  4. Less commonly, a malfunctioning electronic control unit (ECU) can be a serious cause; repair or replacement of the ECU can be costly and typically involves in-depth diagnostics.
  5. A rare but possible cause includes issues with the vehicle's alignment or suspension components, which can affect the steering sensor's performance.

C0387 Repair Costs

Cost Breakdown by Repair Type

Steering Angle Sensor Replacement

Replacing the faulty steering angle sensor with a new OEM part.

  • Total: $150 - $300
  • Success rate: 85%
Wiring Repair

Repairing or replacing damaged wiring leading to the sensor.

  • Total: $100 - $200
  • Success rate: 70%
ECU Reprogramming

Reprogramming or replacing the electronic control unit if it's found to be faulty.

  • Total: $500 - $1500
  • Success rate: 90%
Money-Saving Tips for C0387
  • 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 C0387 Diagnosis Process

Follow these systematic steps to accurately diagnose C0387. 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 steering system (5-10 minutes)

Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion in the steering 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 (10-15 minutes)

Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context (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 or specific diagnostic tools to test the steering angle sensor and its connections (20-30 minutes)

Step 3: Component testing - Use a multimeter or specific diagnostic tools to test the steering angle sensor and its connections (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 angle sensor after repairs and clear fault codes (10-15 minutes)

Step 4: System function test - Verify proper operation of the steering angle sensor after repairs and clear fault 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 5: Step 5: Road test verification - Drive the vehicle under various conditions to confirm the effectiveness of the repair (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to confirm the effectiveness of the repair (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 Angle Sensor Replacement in 2016 Chevrolet Silverado

Vehicle: 2016 Chevrolet Silverado, 45,000 miles

Problem: Customer reported a persistent check engine light and unresponsive steering.

Diagnosis: An OBD2 scan revealed code C0387. Visual inspection showed a damaged steering angle sensor.

Solution: Replaced the steering angle sensor and recalibrated the system.

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

Result: Issue resolved; the check engine light was cleared, and steering responsiveness improved significantly.

Case Study 2: Wiring Repair in 2017 GMC Sierra

Vehicle: 2017 GMC Sierra, 30,000 miles

Problem: Customer experienced erratic steering and dashboard warning lights.

Diagnosis: Diagnostics indicated C0387. Upon inspection, wiring was found frayed and intermittently connected.

Solution: Repaired the damaged wiring and ensured all connections were secure.

Cost: $150 (parts: $50, labor: $100)

Result: Steering behavior normalized, and warning lights no longer appeared.

Diagnose C0387

Use GeekOBD APP for professional diagnosis!

  • Real-time data monitoring
  • Advanced diagnostic features
  • Step-by-step repair guidance
  • Professional-grade analysis
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Code Information

Code: C0387
System: Chassis (ABS, Steering, Suspension)
Severity: HIGH
Category: Chassis Codes