Quick Answer
U0086 means: DTC U0086 indicates a communication failure between vehicle control modules.
Can I drive with U0086? Immediate attention is recommended to prevent further damage.
Common Questions
What does U0086 mean and how does it affect my car?
DTC U0086 indicates a communication failure between vehicle control modules, which can lead to erratic performance, safety issues, and increased repair costs if not addressed promptly.
What are the most common causes of U0086 and how much does it cost to fix?
Common causes include damaged wiring (60%), faulty control modules (25%), and corrosion (10%). Repair costs range from $150 for wiring repairs to $1,200 for module replacements.
Can I drive my car with U0086 or should I stop immediately?
It's advisable to stop driving immediately. Ignoring U0086 can lead to more severe damage and safety risks, as it affects vital vehicle systems.
How can I diagnose U0086 myself using GeekOBD APP?
Use the GeekOBD APP to perform a full system scan, check for other related codes, and view freeze frame data to help identify when and why the U0086 code was triggered.
What vehicles are most commonly affected by U0086?
DTC U0086 is commonly found in vehicles like the 2015-2020 Ford F-150 and Chevrolet Silverado. Check for any recalls or Technical Service Bulletins related to your make and model.
How can I prevent U0086 from happening again?
Regular maintenance is key. Ensure that wiring is intact, connections are clean, and modules are updated. Consider periodic inspections to catch problems early.
What is U0086?
DTC U0086 is a diagnostic trouble code that indicates a communication problem within the Controller Area Network (CAN) in your vehicle. The CAN is a vital system that allows various vehicle modules to communicate with each other, ensuring that systems such as the engine, transmission, and brakes work in harmony. When the U0086 code is triggered, it usually signifies that a module, such as the Engine Control Unit (ECU) or Transmission Control Module (TCM), is not receiving or sending data as expected. This can happen due to a range of issues including damaged wiring, faulty connectors, or even a malfunctioning control module itself. The implications of this code can be severe, as it may lead to erratic vehicle behavior, unexpected engine performance issues, and, in some cases, safety concerns. Ignoring this code can lead to more significant problems down the line, including increased repair costs and potentially dangerous driving conditions. For vehicle owners, understanding this code is crucial to maintaining optimal performance and safety.
System: U - Network (Communication, CAN Bus)
Symptoms
Common symptoms when U0086 is present:
- Check engine light remains illuminated, signaling an issue that needs attention.
- Vehicle may exhibit erratic behavior, such as stalling or hesitation during acceleration, making it difficult to drive safely.
- Fuel economy may decrease significantly, often by 10-15%, due to improper engine management.
- Electrical components may malfunction, such as power windows or radio, indicating a broader electrical issue.
- Warning messages or alerts may pop up on the dashboard, indicating multiple systems are at risk.
Possible Causes
Most common causes of U0086 (ordered by frequency):
- The most common cause of U0086 is damaged wiring or connectors, accounting for approximately 60% of cases. This can occur due to wear and tear or rodent damage.
- A second common cause is a faulty control module, which may fail due to internal circuit issues or software glitches, representing about 25% of U0086 cases.
- Corrosion or poor connections at the module connectors can also lead to communication issues, making up around 10% of diagnosed problems. Regular maintenance can help prevent this.
- Less common but serious causes include a failed power distribution module, which can disrupt communication between several vital systems.
- Rarely, a complete failure of the CAN network itself can occur, resulting in multiple codes being triggered and requiring extensive diagnostic work.
U0086 Repair Costs
Cost Breakdown by Repair Type
Wiring Repair
Repair damaged wiring and connectors to restore proper communication.
- Total: $150 - $400
- Success rate: 90%
Control Module Replacement
Replace faulty control module to resolve communication issues.
- Total: $500 - $1,200
- Success rate: 85%
Money-Saving Tips for U0086
- 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 U0086 Diagnosis Process
Follow these systematic steps to accurately diagnose U0086. 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 (20-30 minutes)
Step 3: Component testing - Use a multimeter or specific diagnostic tools to test suspected components (20-30 minutes).
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).
Step 5: Step 5: Road test verification - Drive vehicle under various conditions to confirm repair success (15-20 minutes)
Step 5: Road test verification - Drive vehicle under various conditions to confirm repair success (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: 2018 Ford F-150 U0086 Diagnosis and Repair
Vehicle: 2018 Ford F-150, 45,000 miles
Problem: Customer reported reduced engine performance and check engine light on.
Diagnosis: Initial OBD2 scan revealed U0086 along with several other codes. Visual inspection showed damaged wiring.
Solution: Repaired damaged wiring and connectors, cleared codes, and performed a successful road test.
Cost: $250 (wiring repair)
Result: Customer reported improved performance and no reoccurrence of the check engine light.
Case Study 2: 2020 Chevrolet Silverado Control Module Replacement
Vehicle: 2020 Chevrolet Silverado, 30,000 miles
Problem: Check engine light illuminated and vehicle exhibited erratic behavior.
Diagnosis: OBD2 scan confirmed U0086. Further testing indicated a faulty control module.
Solution: Replaced the control module, performed system calibration, and cleared codes.
Cost: $850 (module replacement)
Result: Vehicle returned to normal operation with no further issues reported.