U0B71 - Understanding the Communication Line Failure in 2014-2019 Ford Models

Quick Answer

U0B71 means: U0B71 indicates a communication line failure in the vehicle's Body Control Module.

Fix: Check and replace faulty components Cost: $100 - $300 Time: 90-180 minutes

Can I drive with U0B71? Immediate attention is recommended to prevent further electronic issues.

Common Questions

What does U0B71 mean and how does it affect my car?

The U0B71 code signifies a communication failure within the vehicle's Body Control Module, which manages various electronic functions. This can lead to issues with power windows, locks, and dashboard displays. If left unresolved, it may worsen, causing more significant electrical problems.

What are the most common causes of U0B71 and how much does it cost to fix?

Common causes include damaged wiring (60% likelihood), BCM malfunctions, and poor connections. Repair costs can range from $100 for simple wiring fixes to $600 for BCM replacement.

Can I drive my car with U0B71 or should I stop immediately?

It's advisable to stop driving if you notice symptoms associated with U0B71, as this could lead to further electrical issues or a breakdown.

How can I diagnose U0B71 myself using GeekOBD APP?

Using the GeekOBD APP, scan your vehicle to retrieve DTCs and freeze frame data. This will help you understand the context of the failure, allowing for more targeted troubleshooting.

What vehicles are most commonly affected by U0B71?

Commonly affected models include the 2014-2019 Ford F-150, Ford Explorer, and Ford Fusion. Be sure to check for recalls related to BCM issues.

How can I prevent U0B71 from happening again?

Regular maintenance checks on wiring and connectors can help prevent U0B71. Keeping your vehicle's software updated also ensures optimal performance.

What is U0B71?

The U0B71 diagnostic trouble code indicates a communication line failure in the vehicle's network, specifically related to the Body Control Module (BCM). This code typically arises when the BCM detects that it cannot communicate properly with other modules in the vehicle. Communication issues can stem from faulty wiring, poor connections, or issues within the modules themselves. For Ford owners, particularly those driving models from 2014 to 2019, encountering this code may lead to various electronic malfunctions, such as non-functioning power windows, door locks, or dashboard displays. In some cases, the vehicle may experience intermittent failures or complete loss of communication with specific modules. If left unresolved, the impact on vehicle performance can exacerbate, leading to more expensive repairs. Additionally, the illumination of the check engine light will occur, prompting the need for immediate attention. Ultimately, understanding this code and its implications is crucial for maintaining the functionality and reliability of your vehicle's electronic systems.

System: U - Network (Communication, CAN Bus)

Symptoms

Common symptoms when U0B71 is present:

  • Check engine light stays on constantly, indicating a communication error with the BCM.
  • Power windows or door locks may not respond when activated, making it difficult to operate the vehicle.
  • Dashboard displays could malfunction, showing erratic readings or warning lights that shouldn't be illuminated.
  • Intermittent electrical issues could arise, such as lights flickering or audio system failures.
  • In some cases, the vehicle may experience stalling or failure to start due to communication breakdowns between modules.

Possible Causes

Most common causes of U0B71 (ordered by frequency):

  1. The most common cause is damaged wiring or connectors, accounting for about 60% of cases. Corrosion or wear can disrupt communication.
  2. Another significant cause could be a malfunctioning BCM, which may require replacement if internal errors are detected.
  3. Poor ground connections can also lead to U0B71, and ensuring proper grounding can prevent reoccurrence.
  4. Less common but serious is a failure within the CAN bus system, which could affect all electronic functions in the vehicle.
  5. A rare cause might be software glitches within the BCM that require a firmware update to resolve.

U0B71 Repair Costs

Cost Breakdown by Repair Type

Wiring Repair

Repair or replacement of damaged wiring or connectors.

  • Total: $100 - $300
  • Success rate: 85%
BCM Replacement

Replacement of the Body Control Module if malfunctioning.

  • Total: $300 - $600
  • Success rate: 90%
Software Update

Performing a software update on the BCM to fix glitches.

  • Total: $50 - $150
  • Success rate: 70%
Money-Saving Tips for U0B71
  • 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 U0B71 Diagnosis Process

Follow these systematic steps to accurately diagnose U0B71. 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).

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 suspected components (20-30 minutes)

Step 3: Component testing - Use a multimeter or specific diagnostic tools to test suspected components (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 after repairs and clear codes (10-15 minutes)

Step 4: System function test - Verify proper operation after repairs and clear 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 repair success (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to 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: 2017 Ford F-150 Communication Issue

Vehicle: 2017 Ford F-150, 45,000 miles

Problem: Customer reported power windows and door locks not functioning.

Diagnosis: Visual inspection revealed corroded connectors in the wiring harness.

Solution: Repaired wiring and replaced connectors, restoring communication.

Cost: $250

Result: All electronic functions restored, customer reported satisfaction.

Case Study 2: 2018 Ford Explorer BCM Replacement

Vehicle: 2018 Ford Explorer, 30,000 miles

Problem: Check engine light on with multiple electronic failures.

Diagnosis: OBD2 scan revealed U0B71 and confirmed a faulty BCM.

Solution: Replaced the BCM and updated software.

Cost: $450

Result: Vehicle functioning properly with no warning lights post-repair.

Diagnose U0B71

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: U0B71
System: Network (Communication, CAN Bus)
Severity: HIGH
Category: Network Codes