B0387 - Understanding the Body Control Module (BCM) Code in 2015-2018 Honda Civic

Quick Answer

B0387 means: B0387 indicates a malfunction in the right rear door latch circuit, affecting the Body Control Module.

Fix: Check and replace faulty components Cost: $150 - $250 Time: 90-180 minutes

Can I drive with B0387? While not immediately dangerous, it’s advisable to address this code promptly to avoid further electrical issues.

Common Questions

What does B0387 mean and how does it affect my car?

The B0387 code indicates a problem with the right rear door latch circuit, which can affect your car's electrical systems, including door locks and interior lights. Ignoring this code can lead to further electrical issues and potential safety risks.

What are the most common causes of B0387 and how much does it cost to fix?

Common causes of B0387 include a faulty door latch sensor, wiring issues, or a malfunctioning BCM. Repair costs typically range from $100 to $250, depending on the specific issue and parts required.

Can I drive my car with B0387 or should I stop immediately?

While it's not an immediate danger, you should address the B0387 code soon to prevent further electrical problems. Driving with unresolved electrical issues can lead to greater costs and safety risks.

How can I diagnose B0387 myself using GeekOBD APP?

To diagnose B0387 using the GeekOBD APP, start by scanning the OBD2 system for codes. Review the freeze frame data to analyze the conditions under which the code was triggered. Follow the diagnostic steps to test the door latch and wiring.

What vehicles are most commonly affected by B0387?

The B0387 code is frequently seen in vehicles like the 2015-2018 Honda Civic, 2016-2019 Toyota Corolla, and similar models. Always check for recalls or TSBs related to electrical issues.

How can I prevent B0387 from happening again?

Regular maintenance, including checking door latches and wiring for wear, can help prevent B0387. Additionally, avoiding aftermarket modifications that affect electrical systems can safeguard against future issues.

What is B0387?

The Diagnostic Trouble Code (DTC) B0387 is related to issues with the Body Control Module (BCM) in certain vehicles, notably affecting models like the 2015-2018 Honda Civic. This code indicates that there is a problem with the right rear door latch circuit, which can disrupt various electrical systems in your vehicle. The BCM is responsible for managing electrical systems such as lighting, door locks, and even the alarm system. When the B0387 code is triggered, it means the BCM has detected an inconsistency in the right rear door latch input, which can lead to several functional issues. For instance, you might notice that the door locks don't operate correctly, the interior lights may stay on, or other electrical features might fail to work as intended. If left unaddressed, these issues could escalate, impacting your vehicle’s overall performance and safety. Understanding this code is crucial for timely repairs, ensuring that your vehicle remains in good working order and that you avoid more costly repairs in the future.

System: B - Body (Airbags, Lighting, Security, Climate Control)

Symptoms

Common symptoms when B0387 is present:

  • Check engine light stays on constantly, indicating a persistent issue with the BCM.
  • Interior lights remain illuminated even after the vehicle is turned off, suggesting a malfunction in the door latch.
  • Power door locks fail to respond correctly, causing inconvenience and security concerns.
  • Door ajar warning light may illuminate on the dashboard, leading to confusion about whether the door is actually closed.
  • Inconsistent operation of other electrical features like windows or mirrors, directly tied to BCM functionality.

Possible Causes

Most common causes of B0387 (ordered by frequency):

  1. Faulty right rear door latch sensor - This is the most common cause, accounting for approximately 60% of B0387 cases. The latch sensor may fail due to wear and tear or water exposure.
  2. Wiring issues - Damaged or corroded wiring in the door harness can lead to intermittent connections, causing the BCM to trigger the code.
  3. BCM malfunction - Although less common, a failure in the BCM itself can lead to erroneous codes like B0387. Regular diagnostics can help prevent this.
  4. Poor grounding - If the grounding point for the BCM is compromised, it can produce false readings and lead to code B0387.
  5. Aftermarket modifications - Installation of non-OEM electrical components can interfere with the BCM's operation, potentially causing this code.

B0387 Repair Costs

Cost Breakdown by Repair Type

Right Rear Door Latch Replacement

Replacing the faulty door latch sensor with an OEM part to ensure compatibility and reliability.

  • Total: $150 - $250
  • Success rate: 85%
Wiring Repair

Repairing or replacing damaged wiring in the door harness to restore proper electrical function.

  • Total: $100 - $200
  • Success rate: 75%
Money-Saving Tips for B0387
  • 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 B0387 Diagnosis Process

Follow these systematic steps to accurately diagnose B0387. 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 right rear door area (5-10 minutes)

Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion in the right rear door area (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 - Use the app to retrieve all codes and freeze frame data, helping you understand the context of the fault (10-15 minutes)

Step 2: OBD2 scan with GeekOBD APP - Use the app to retrieve all codes and freeze frame data, helping you understand the context of the fault (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 - Utilize a multimeter to test the right rear door latch sensor and inspect the wiring harness for continuity (20-30 minutes)

Step 3: Component testing - Utilize a multimeter to test the right rear door latch sensor and inspect the wiring harness for continuity (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 - After any repairs, verify the proper operation of the door latch and clear the codes using the GeekOBD APP (10-15 minutes)

Step 4: System function test - After any repairs, verify the proper operation of the door latch 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 that the B0387 code does not return (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to confirm that the B0387 code does not return (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 B0387 Door Latch Replacement

Vehicle: 2016 Honda Civic, 45,000 miles

Problem: Customer reported that the interior lights stayed on and the power door locks were non-functional.

Diagnosis: Diagnostic scanning revealed DTC B0387. Visual inspection showed corrosion on the right rear door latch connector.

Solution: Replaced the right rear door latch sensor and cleaned all connectors to ensure proper functionality.

Cost: $200 (including parts and labor)

Result: Customer reported all electrical functions restored, and no further issues after road testing.

Case Study 2: Toyota Corolla Wiring Issue Resolution

Vehicle: 2017 Toyota Corolla, 30,000 miles

Problem: Driver experienced intermittent door lock failures and dashboard warning lights.

Diagnosis: OBD2 scan confirmed B0387. A thorough inspection of the wiring harness revealed frayed wires.

Solution: Repaired the damaged wiring and secured connections, ensuring proper grounding.

Cost: $150 (repair only, parts included)

Result: Post-repair tests showed consistent performance with no reappearance of the code.

Diagnose B0387

Use GeekOBD APP for professional diagnosis!

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

Code: B0387
System: Body (Airbags, Lighting, Security, Climate Control)
Severity: MEDIUM
Category: Body Codes