Quick Answer
B0979 means: DTC B0979 signals a battery energy control module fault.
Can I drive with B0979? Immediate attention is recommended to prevent further damage.
Common Questions
What does B0979 mean and how does it affect my car?
The B0979 code indicates a fault in the battery energy control module, crucial for managing battery performance. Ignoring it can lead to performance issues, reduced fuel efficiency, and potential stalling.
What are the most common causes of B0979 and how much does it cost to fix?
The most typical causes include a faulty battery control module and corroded terminals. Repair costs can range from $50 for terminal cleaning to $800 for module replacement.
Can I drive my car with B0979 or should I stop immediately?
While you may still drive, it’s not recommended as this code can lead to significant power loss and engine performance issues. It's best to address it promptly.
How can I diagnose B0979 myself using GeekOBD APP?
Using the GeekOBD APP, you can perform a full OBD2 scan, check for any related codes, and access freeze frame data to understand the problem better.
What vehicles are most commonly affected by B0979?
This code is frequently seen in 2015-2018 Ford F-150 models, as well as some hybrid vehicles. Be sure to check for any recalls or Technical Service Bulletins related to this code.
How can I prevent B0979 from happening again?
Regular battery maintenance, including cleaning terminals and checking connections, along with periodic system diagnostics, can help keep issues at bay.
What is B0979?
DTC B0979 refers to a code that indicates a fault in the vehicle's battery energy control module (BECM). This code is primarily seen in vehicles equipped with advanced energy management systems, such as hybrid and electric models, but can also appear in conventional vehicles with complex electrical systems. When the BECM detects that the battery is not functioning optimally or is unable to communicate effectively with the engine control module (ECM), it triggers this diagnostic trouble code. In practical terms, this can lead to various performance issues such as reduced engine efficiency, misfires, or even stalling. Commonly found in 2015-2018 Ford F-150 models, this issue can arise due to a multitude of reasons including worn-out battery terminals, faulty wiring, or an aging battery itself. If you ignore this code, it could lead to more severe problems like complete battery failure or additional strain on the engine, potentially resulting in costly repairs down the road. Therefore, understanding the implications of DTC B0979 and addressing it promptly is crucial for vehicle longevity and performance.
System: B - Body (Airbags, Lighting, Security, Climate Control)
Symptoms
Common symptoms when B0979 is present:
- Check engine light illuminates and remains lit, indicating a serious issue that needs immediate investigation.
- Engine may hesitate or struggle during acceleration, leading to a less responsive driving experience.
- Fuel economy may decrease significantly, potentially by 10-15%, which can increase your overall driving costs.
- Unusual electrical behaviors, such as flickering lights or malfunctioning electronic accessories, may occur.
- The vehicle may enter a 'limp' mode, restricting engine performance to prevent further damage.
Possible Causes
Most common causes of B0979 (ordered by frequency):
- The most common cause of DTC B0979 is a faulty battery energy control module, which occurs in about 50% of cases. This can be due to age, wear and tear, or a manufacturing defect.
- Another likely cause is corroded or loose battery terminals, which can disrupt electrical flow and account for 25% of the issues related to this code.
- Faulty wiring or connectors related to the battery can also trigger this code. Regular inspections can help prevent this by catching issues early.
- Less common, but serious, is a failing battery, which can lead to complete loss of power if not addressed. This scenario occurs in about 15% of cases.
- A malfunctioning ECM can rarely cause B0979, but this issue, while uncommon, can be quite costly to repair if diagnosed.
B0979 Repair Costs
Cost Breakdown by Repair Type
Battery Energy Control Module Replacement
Replacing the faulty battery energy control module to restore proper function.
- Total: $400 - $800
- Success rate: 90%
Battery Terminal Cleaning and Replacement
Cleaning or replacing corroded battery terminals to ensure proper electrical connectivity.
- Total: $50 - $150
- Success rate: 85%
Wiring Repair
Repairing or replacing damaged wiring associated with the battery system.
- Total: $100 - $300
- Success rate: 70%
Money-Saving Tips for B0979
- 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 B0979 Diagnosis Process
Follow these systematic steps to accurately diagnose B0979. 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).
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).
Step 3: Step 3: Component testing - Use a multimeter to check battery voltage and continuity in wiring (20-30 minutes)
Step 3: Component testing - Use a multimeter to check battery voltage and continuity in wiring (20-30 minutes).
Step 4: Step 4: System function test - After repairs, verify proper operation and clear codes to ensure the issue is resolved (10-15 minutes)
Step 4: System function test - After repairs, verify proper operation and clear codes to ensure the issue is resolved (10-15 minutes).
Step 5: Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success and monitor for recurrences (15-20 minutes)
Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success and monitor for recurrences (15-20 minutes).
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: Battery Energy Control Module Replacement on 2017 Ford F-150
Vehicle: 2017 Ford F-150, 45,000 miles
Problem: Customer reported check engine light and decreased fuel efficiency.
Diagnosis: After scanning with GeekOBD APP, B0979 was confirmed. Visual inspection revealed corroded terminals and a failing module.
Solution: Replaced the battery energy control module and cleaned battery terminals.
Cost: $650 (module $600, labor $50)
Result: Customer reported improved performance and fuel economy after repairs.
Case Study 2: Wiring Repair on 2016 Ford Fusion
Vehicle: 2016 Ford Fusion, 60,000 miles
Problem: Vehicle exhibited hesitation during acceleration and illuminated check engine light.
Diagnosis: Found B0979 during diagnostics; traced issue to a damaged wiring harness.
Solution: Repaired the wiring and performed a system function test.
Cost: $200 (labor $100, parts $100)
Result: Customer experienced smooth acceleration and no further check engine light.