Quick Answer
U079B means: U079B indicates a communication error between vehicle control modules.
Can I drive with U079B? Immediate action required to prevent further damage and ensure vehicle safety.
Common Questions
What does U079B mean and how does it affect my car?
The U079B code indicates a communication failure between your vehicle's control modules, which can lead to a variety of performance issues. This may result in problems like erratic engine behavior, failure of electronic features, and increased fuel consumption. It's crucial to address this issue promptly to avoid complications and ensure safe vehicle operation.
What are the most common causes of U079B and how much does it cost to fix?
Common causes of U079B include damaged wiring (60% likelihood), software glitches, and failed control modules. Repair costs can range from $150 for wiring repairs to over $1,200 for module replacements, depending on the issue's complexity.
Can I drive my car with U079B or should I stop immediately?
While you may be able to drive your car with a U079B code, it's not advisable. Doing so can lead to further damage, including potential stalling or failure of critical systems. It's best to have the vehicle inspected as soon as possible.
How can I diagnose U079B myself using GeekOBD APP?
Using the GeekOBD APP, you can perform a quick OBD2 scan to retrieve all codes and freeze frame data. Look for additional DTCs that may indicate the source of the problem. The app can also help you monitor live data for the affected modules, allowing for better diagnostic insights.
What vehicles are most commonly affected by U079B?
The U079B code is frequently encountered in 2015-2018 Ford F-150s and Chevrolet Silverado models. These vehicles often experience issues related to communication between their control modules, particularly after software updates.
How can I prevent U079B from happening again?
To prevent U079B from reoccurring, regularly inspect your vehicle's wiring and connectors for wear or corrosion. Additionally, ensure that all software updates are performed by qualified technicians and avoid installing aftermarket electronic devices that could interfere with the vehicle's systems.
What is U079B?
The U079B diagnostic trouble code (DTC) indicates a communication issue between the vehicle's control modules, specifically pointing to a malfunction in the data bus. This code is particularly relevant for various models from manufacturers like Ford and Chevrolet, especially those produced between 2015 and 2020. When the U079B code is triggered, it suggests that the vehicle's electronic control unit (ECU) is unable to communicate effectively with other modules, such as the engine control module (ECM), transmission control module (TCM), or other critical systems. This can lead to a range of operational issues, including erratic behavior of the vehicle's electrical components, a decrease in fuel efficiency, and, in some cases, stalling or failure to start. Car owners may notice warning lights on the dashboard, including the check engine light, and experience symptoms like inconsistent power delivery or failure of electronic features like power windows and central locking systems. Addressing this issue promptly is crucial, as prolonged neglect can lead to further complications, including total system failure and costly repairs. Understanding what the U079B code means and how it affects your vehicle can help you take proactive measures to maintain its performance.
System: U - Network (Communication, CAN Bus)
Symptoms
Common symptoms when U079B is present:
- Check engine light stays on constantly, indicating a persistent communication error that needs immediate attention.
- Engine hesitates during acceleration, making driving unpredictable and potentially dangerous.
- Fuel economy decreased by 10-15%, leading to increased operational costs and frequent stops at the gas station.
- Power windows may fail to operate correctly, affecting the vehicle's comfort and functionality.
- Central locking system may malfunction, raising security concerns for vehicle owners.
Possible Causes
Most common causes of U079B (ordered by frequency):
- The most common cause of U079B is damaged or corroded wiring in the communication circuits, with a likelihood of around 60%. Regular checks on wiring integrity can prevent this issue.
- A second cause could be software glitches within the control modules, which may occur after a software update or due to a faulty module. Keeping software up to date is essential.
- Thirdly, a failed control module itself might be the culprit, which can often be prevented by ensuring proper maintenance and avoiding water damage.
- Less common, but serious, causes could include a short circuit in the wiring harness, which can lead to extensive damage if not addressed quickly.
- A rare but possible cause includes external interference from aftermarket electronic devices that disrupt the vehicle's communication system.
U079B Repair Costs
Cost Breakdown by Repair Type
Wiring Repair
Repair or replacement of damaged wiring and connectors in the communication circuit.
- Total: $150 - $500
- Success rate: 85%
Control Module Replacement
Replacing a faulty control module that has failed to communicate properly.
- Total: $400 - $1,200
- Success rate: 90%
Software Update
Performing a software update to correct communication issues and bugs.
- Total: $50 - $150
- Success rate: 75%
Money-Saving Tips for U079B
- 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 U079B Diagnosis Process
Follow these systematic steps to accurately diagnose U079B. 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 or specific diagnostic tools to test suspected components, focusing on the communication lines (20-30 minutes)
Step 3: Component testing - Use a multimeter or specific diagnostic tools to test suspected components, focusing on the communication lines (20-30 minutes).
Step 4: Step 4: System function test - Verify proper operation after repairs and clear codes, ensuring that all modules are communicating effectively (10-15 minutes)
Step 4: System function test - Verify proper operation after repairs and clear codes, ensuring that all modules are communicating effectively (10-15 minutes).
Step 5: Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success, checking for any reoccurrence of the code (15-20 minutes)
Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success, checking for any reoccurrence of the code (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: Ford F-150 U079B Code Diagnosis and Repair
Vehicle: 2017 Ford F-150, 45,000 miles
Problem: Customer reported a persistent check engine light and poor acceleration.
Diagnosis: Diagnostic scan revealed U079B along with several other codes indicating communication errors. Visual inspection showed corroded wiring in the data bus.
Solution: Repaired the damaged wiring and tested all control modules for proper functionality.
Cost: $350 (wiring repair and diagnostic fee)
Result: After repairs, the check engine light was cleared, and the vehicle performed efficiently during a road test.
Case Study 2: Chevrolet Silverado Control Module Replacement
Vehicle: 2018 Chevrolet Silverado, 30,000 miles
Problem: Owner experienced sporadic engine stalls and electrical issues.
Diagnosis: U079B code was found alongside an error indicating a failed engine control module. Testing confirmed the module was not responding.
Solution: Replaced the faulty control module and updated the vehicle's software.
Cost: $1,000 (module replacement and labor)
Result: Vehicle performance improved significantly, with no further issues reported after the repair.