C0B9C - Understanding the C0B9C Trouble Code in 2016-2020 Ford Explorer and Other Vehicles

Quick Answer

C0B9C means: C0B9C indicates a fault in the body control module related to the rear lighting circuit.

Fix: Check and replace faulty components Cost: $300 - $800 Time: 90-180 minutes

Can I drive with C0B9C? Immediate attention is advised to ensure safety and proper vehicle function.

Common Questions

What does C0B9C mean and how does it affect my car?

C0B9C indicates a fault in the body control module related to the rear lighting circuit. This issue can lead to malfunctioning lights, which poses safety risks while driving. It can also affect the vehicle's performance and cause it to enter limp mode, reducing engine power.

What are the most common causes of C0B9C and how much does it cost to fix?

Common causes of C0B9C include a faulty BCM (60% likelihood, $300 - $800), wiring issues (25% likelihood, $100 - $300), and blown fuses (rare, $10 - $50). Repair costs vary based on the specific issue detected.

Can I drive my car with C0B9C or should I stop immediately?

It is not advisable to drive with C0B9C. The malfunctioning lights could lead to a safety hazard, especially in low visibility. It is best to address the issue promptly to ensure safe driving conditions.

How can I diagnose C0B9C myself using GeekOBD APP?

Using the GeekOBD APP, you can scan for diagnostic trouble codes and retrieve freeze frame data. Look for any codes related to the BCM or rear lighting, and follow diagnostic steps to identify any wiring or connector issues.

What vehicles are most commonly affected by C0B9C?

C0B9C is frequently reported in vehicles like the 2016-2020 Ford Explorer. Other models may also experience this code, particularly those with similar BCM configurations.

How can I prevent C0B9C from happening again?

Regular maintenance is key. Inspect wiring and connectors for wear, ensure the vehicle is free of moisture, and periodically check the BCM for updates or issues to prevent C0B9C from recurring.

What is C0B9C?

The Diagnostic Trouble Code (DTC) C0B9C refers to a specific issue related to the vehicle's body control module (BCM) or the communication between the BCM and other modules. This code often indicates that the BCM has detected a fault in the rear lighting circuit, which may affect various features such as tail lights, brake lights, and even turn signals. When C0B9C is triggered, it can lead to malfunctioning lights or lights that do not operate at all, posing safety risks while driving at night or in low visibility conditions. Furthermore, this code may also cause the vehicle's system to enter limp mode, limiting engine performance to prevent further damage. In practical terms, if you see the C0B9C code on your OBD2 scanner, it is crucial to address it promptly, as ignoring it may lead to more extensive electrical issues or even complete failure of the rear lighting system. Owners of affected vehicles, particularly those from Ford, should be aware that this issue has been noted in models such as the 2016-2020 Ford Explorer, where wiring harness problems or BCM failures are common. Regular maintenance and inspection of the vehicle's electrical systems can help prevent the occurrence of this code.

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

Symptoms

Common symptoms when C0B9C is present:

  • Check engine light illuminated or warning light for rear lights stays on constantly, indicating an issue with the lighting system.
  • Rear brake lights may not function correctly, leading to unsafe driving conditions, especially at night.
  • Tail lights flicker or do not illuminate at all, which can cause confusion for other drivers and potential accidents.
  • Dashboard warning messages may appear, such as 'Check Rear Lights' or similar alerts.
  • Inconsistent behavior of turn signals, which may not flash or operate intermittently, increasing the risk of accidents.

Possible Causes

Most common causes of C0B9C (ordered by frequency):

  1. The most common cause of C0B9C is a faulty body control module (BCM), which occurs in about 60% of cases. This may be due to water damage or electrical shorts.
  2. Wiring issues such as frayed wires or poor connections can account for around 25% of C0B9C occurrences, often due to wear and tear or rodent damage.
  3. Connector problems, where the BCM connects to the lighting circuit, can cause communication failures, making up about 10% of cases. Regular inspections can help prevent this.
  4. Less commonly, a blown fuse in the lighting circuit may lead to this code, which is an easy fix but should be diagnosed properly.
  5. Rarely, a software glitch in the BCM can trigger C0B9C, requiring a software update or reprogramming to resolve.

C0B9C Repair Costs

Cost Breakdown by Repair Type

Body Control Module Replacement

Replacing the faulty BCM with a new or refurbished unit to restore proper function.

  • Total: $300 - $800
  • Success rate: 85%
Wiring Repair

Fixing damaged wiring or connectors that affect the rear lighting circuit.

  • Total: $100 - $300
  • Success rate: 90%
Fuse Replacement

Replacing blown fuses that may cause lighting issues.

  • Total: $10 - $50
  • Success rate: 95%
Money-Saving Tips for C0B9C
  • 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 C0B9C Diagnosis Process

Follow these systematic steps to accurately diagnose C0B9C. 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 (5-10 minutes)

Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion (5-10 minutes). Look around the BCM and rear light assemblies.

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 GeekOBD APP to retrieve all codes and freeze frame data to understand the fault context (10-15 minutes)

Step 2: OBD2 scan with GeekOBD APP - Use the GeekOBD APP to retrieve all codes and freeze frame data to understand the fault context (10-15 minutes). This helps identify if C0B9C is a standalone issue or part of a larger problem.

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 suspected components such as the BCM and rear light bulbs (20-30 minutes)

Step 3: Component testing - Use a multimeter or specific diagnostic tools to test suspected components such as the BCM and rear light bulbs (20-30 minutes). Ensure all electrical connections are secure.

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 making repairs, test all rear lights and clear codes to verify proper operation (10-15 minutes)

Step 4: System function test - After making repairs, test all rear lights and clear codes to verify proper operation (10-15 minutes). Check for any new codes that may appear.

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 repair success and ensure all functions are working correctly (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success and ensure all functions are working correctly (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: 2018 Ford Explorer Lighting Malfunction

Vehicle: 2018 Ford Explorer, 45,000 miles

Problem: Customer reported that rear brake lights were not functioning, and the dashboard displayed a 'Check Rear Lights' warning.

Diagnosis: After an OBD2 scan using GeekOBD APP, C0B9C was retrieved. Visual inspection revealed corroded connectors at the rear light assembly.

Solution: Replaced the corroded connectors and cleaned the wiring harness. Cleared the DTC and confirmed proper light operation.

Cost: $150 (parts and labor)

Result: Customer reported successful repair with no further issues.

Case Study 2: 2017 Ford Explorer BCM Replacement

Vehicle: 2017 Ford Explorer, 60,000 miles

Problem: Vehicle experienced intermittent rear light failures, and C0B9C was present in the system.

Diagnosis: After thorough testing, the BCM was found to be malfunctioning due to moisture damage.

Solution: Replaced the BCM with a new unit and updated the software. Confirmed all lights were functioning post-repair.

Cost: $600 (parts and labor)

Result: Follow-up showed no issues, and the customer was satisfied with the repair.

Diagnose C0B9C

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: C0B9C
System: Chassis (ABS, Steering, Suspension)
Severity: HIGH
Category: Chassis Codes