U0A39 - Understanding DTC U0A39: Common Issues in 2018-2020 Ford F-150 and Other Models

Quick Answer

U0A39 means: U0A39 indicates a communication failure between the central gateway module and battery energy control module.

Fix: Check and replace faulty components Cost: $150 - $400 Time: 90-180 minutes

Can I drive with U0A39? Immediate attention is recommended to prevent further electrical issues.

Common Questions

What does U0A39 mean and how does it affect my car?

DTC U0A39 indicates a failure in communication between the central gateway module and the battery energy control module. This can lead to significant electrical issues, affecting the vehicle's ability to start, as well as the performance of various electronic components. If ignored, it may result in a complete shutdown of the vehicle or further electrical malfunctions.

What are the most common causes of U0A39 and how much does it cost to fix?

The most common cause of U0A39 is wiring damage, which can range from $150 to $400 for repairs. Software issues and module replacements can also be factors, with costs ranging from $500 to $1,200 depending on the specific problem.

Can I drive my car with U0A39 or should I stop immediately?

It is advisable to stop driving your vehicle if you see the U0A39 code, as it indicates potential electrical issues that could lead to a breakdown. Continuing to drive can exacerbate the problem and lead to more costly repairs.

How can I diagnose U0A39 myself using GeekOBD APP?

To diagnose U0A39 with the GeekOBD APP, first connect the app to your vehicle's OBD2 port. Run a full scan to retrieve all codes, including U0A39. Review freeze frame data to understand the conditions under which the code was triggered, and check for any related codes that may provide additional context.

What vehicles are most commonly affected by U0A39?

DTC U0A39 is often seen in 2018-2020 Ford F-150 models, but it can also affect other vehicles from various manufacturers that utilize similar electrical architecture. Always check for any recalls or technical service bulletins related to your specific model.

How can I prevent U0A39 from happening again?

Regular maintenance of your vehicle's electrical system can help prevent DTC U0A39. This includes checking wiring and connectors for wear and tear, ensuring proper software updates, and using protective measures against corrosion.

What is U0A39?

DTC U0A39 is a diagnostic trouble code indicating a communication issue between the vehicle's central gateway module and the battery energy control module. This code can arise in various vehicles, but it is particularly noted in models such as the 2018-2020 Ford F-150. When this code appears, it suggests that the modules responsible for managing battery energy and power distribution are not communicating effectively. This communication breakdown can result from wiring issues, software glitches, or faults within the modules themselves. If left unaddressed, U0A39 can lead to more severe electrical problems, affecting the vehicle's performance and battery management systems. Drivers may experience issues such as erratic electrical behavior, battery drain, or even complete vehicle shutdown in extreme cases. Understanding the implications of this code is crucial for maintaining the health of your vehicle's electrical systems and ensuring reliable operation in the long run.

System: U - Network (Communication, CAN Bus)

Symptoms

Common symptoms when U0A39 is present:

  • The check engine light illuminates and remains on, indicating a persistent issue that requires attention.
  • Electrical components may behave erratically, such as headlights flickering or infotainment systems rebooting unexpectedly.
  • There might be significant battery drain, with the vehicle failing to start after sitting for a short period.
  • The vehicle may enter a reduced power mode, limiting acceleration and overall performance during driving.
  • Dashboard warning lights may activate, including battery or charging system alerts, signaling potential failure.

Possible Causes

Most common causes of U0A39 (ordered by frequency):

  1. The most common cause of U0A39 is damaged wiring or connectors between the central gateway module and the battery energy control module, with a likelihood of about 60%.
  2. Software glitches within the vehicle’s modules can also trigger this code, often occurring after updates or when replacing components.
  3. Faulty modules, such as a malfunctioning battery energy control module, can lead to communication failures; regular diagnostics can help prevent these issues.
  4. A less common but serious cause could be a short circuit in the electrical system, which can result in extensive damage if not addressed promptly.
  5. Rarely, external factors such as water intrusion or corrosion at connector points may cause intermittent communication problems.

U0A39 Repair Costs

Cost Breakdown by Repair Type

Wiring Repair

Repairing or replacing damaged wiring and connectors between the modules.

  • Total: $150 - $400
  • Success rate: 85%
Module Replacement

Replacing the faulty battery energy control module if it is determined to be the cause of the issue.

  • Total: $500 - $1,200
  • Success rate: 90%
Money-Saving Tips for U0A39
  • 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 U0A39 Diagnosis Process

Follow these systematic steps to accurately diagnose U0A39. Each step builds on the previous one to ensure accurate diagnosis.

Step 1: Step 1: Perform an initial visual inspection of the wiring and connectors associated with the central gateway module and battery energy control module, looking for damage or corrosion (5-10 minutes)

Step 1: Perform an initial visual inspection of the wiring and connectors associated with the central gateway module and battery energy control module, looking for damage 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: Use the GeekOBD APP to perform an OBD2 scan, retrieving all diagnostic codes and freeze frame data to gather context on the U0A39 code (10-15 minutes)

Step 2: Use the GeekOBD APP to perform an OBD2 scan, retrieving all diagnostic codes and freeze frame data to gather context on the U0A39 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: Conduct component testing with a multimeter to verify the integrity of voltage and ground connections at the affected modules (20-30 minutes)

Step 3: Conduct component testing with a multimeter to verify the integrity of voltage and ground connections at the affected modules (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: After any repairs, perform a system function test to ensure that the modules are communicating correctly and clear the codes from the memory (10-15 minutes)

Step 4: After any repairs, perform a system function test to ensure that the modules are communicating correctly and clear the codes from the memory (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: Execute a road test under various driving conditions to confirm that the issue has been resolved and check for reoccurrence of the U0A39 code (15-20 minutes)

Step 5: Execute a road test under various driving conditions to confirm that the issue has been resolved and check for reoccurrence of the U0A39 code (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: 2019 Ford F-150 Electrical Issue

Vehicle: 2019 Ford F-150, 45,000 miles

Problem: Customer reported check engine light and recurring battery drain.

Diagnosis: Initial inspection revealed corroded connectors between the gateway and battery control module.

Solution: Replaced corroded connectors and performed a system reset.

Cost: $250

Result: The check engine light was resolved, and the vehicle operated normally post-repair.

Case Study 2: 2018 Ford Explorer Communication Failure

Vehicle: 2018 Ford Explorer, 30,000 miles

Problem: Driver experienced erratic electrical behavior and dashboard warnings.

Diagnosis: Diagnostic scan revealed U0A39; further testing indicated a faulty battery energy control module.

Solution: Replaced the battery energy control module and updated software.

Cost: $900

Result: All electrical functions were restored to normal operation.

Diagnose U0A39

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: U0A39
System: Network (Communication, CAN Bus)
Severity: HIGH
Category: Network Codes