Quick Answer
U0140 means: U0140 indicates a loss of communication with the Body Control Module, affecting vehicle electronics.
Can I drive with U0140? Immediate diagnosis and repair are advisable to ensure vehicle safety and functionality.
Common Questions
What does U0140 mean and how does it affect my car?
The U0140 code signifies a communication loss between the ECM and BCM, potentially affecting various electronic systems. If unresolved, this could lead to widespread electrical issues that hinder your vehicle's performance.
What are the most common causes of U0140 and how much does it cost to fix?
Common causes include damaged wiring (60% likelihood), faulty BCMs, and poor electrical connections. Fixing these issues can range from $100 for wiring repairs to $600 for BCM replacement.
Can I drive my car with U0140 or should I stop immediately?
While you may be able to drive the vehicle, it's not recommended as it could lead to further electrical issues. It's best to diagnose and repair the problem as soon as possible.
How can I diagnose U0140 myself using GeekOBD APP?
Using the GeekOBD APP, you can scan for trouble codes and view freeze frame data, which helps you understand the context of the U0140 code. Pay attention to any additional codes that may point to related issues.
What vehicles are most commonly affected by U0140?
Commonly affected vehicles include the 2010-2017 Chevrolet Malibu, 2013-2016 Dodge Dart, and various models from Ford and Chrysler. Always check for recalls related to the BCM for specific models.
How can I prevent U0140 from happening again?
Regularly inspect electrical connections and wiring for wear, keep the BCM updated with software, and address any electrical issues promptly to prevent future occurrences.
What is U0140?
The DTC U0140 code indicates a communication loss between the Engine Control Module (ECM) and the Body Control Module (BCM). This issue can arise from a variety of reasons, including wiring problems, poor connections, or failures in one of the modules. When the ECM cannot communicate with the BCM, it can lead to a range of symptoms, including issues with vehicle accessories, lights, or even the engine not starting properly. In practical terms, drivers may notice that certain electronic systems, like power windows or door locks, malfunction or fail to respond. Moreover, this code could trigger the Check Engine light and may result in the car entering limp mode to protect the engine from further issues. In vehicles like the 2010-2017 Chevrolet Malibu and 2013-2016 Dodge Dart, it's crucial to diagnose and address the U0140 code promptly to avoid further complications that could affect vehicle safety and drivability.
System: U - Network (Communication, CAN Bus)
Symptoms
Common symptoms when U0140 is present:
- The Check Engine light remains illuminated, indicating a potential issue with vehicle communication systems.
- Power windows and door locks may become unresponsive, leading to inconvenience when trying to access or use your vehicle.
- Engine may hesitate during acceleration, which can be worrying for drivers, especially during merging or passing situations.
- Dashboard indicators may behave erratically, such as warning lights flickering or failing to turn on when expected.
- Inconsistent operation of vehicle features, like windshield wipers or headlights, can occur, impacting safe driving conditions.
Possible Causes
Most common causes of U0140 (ordered by frequency):
- The most common cause is damaged wiring or loose connections, which account for about 60% of cases. Regular wear and tear can lead to these issues, especially in older vehicles.
- A malfunctioning Body Control Module (BCM) is the second most common cause, typically due to internal failure or software glitches. Regular updates and diagnostics can help prevent this.
- Poor grounds or corroded connectors can also lead to communication issues, emphasizing the importance of maintaining clean and secure electrical connections.
- Less common but serious causes include a failed Engine Control Module (ECM), which can significantly impact vehicle operation and require immediate professional attention.
- A rare cause could be a factory recall related to the BCM, which may necessitate software updates or part replacements at no cost to the owner.
U0140 Repair Costs
Cost Breakdown by Repair Type
Wiring Repair
Repairing damaged wiring or loose connections to restore communication between modules.
- Total: $100 - $300
- Success rate: 85%
BCM Replacement
Replacing a faulty Body Control Module if it's determined to be the root cause of the communication failure.
- Total: $300 - $600
- Success rate: 90%
Money-Saving Tips for U0140
- 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 U0140 Diagnosis Process
Follow these systematic steps to accurately diagnose U0140. Each step builds on the previous one to ensure accurate diagnosis.
Step 1: Step 1: Conduct an initial visual inspection, looking for any obvious signs of damage, such as frayed wiring, loose connections, or corrosion around the BCM and ECM (5-10 minutes)
Step 1: Conduct an initial visual inspection, looking for any obvious signs of damage, such as frayed wiring, loose connections, or corrosion around the BCM and ECM (5-10 minutes).
Step 2: Step 2: Use an OBD2 scan tool or the GeekOBD APP to retrieve all trouble codes and freeze frame data to gather context for the U0140 code (10-15 minutes)
Step 2: Use an OBD2 scan tool or the GeekOBD APP to retrieve all trouble codes and freeze frame data to gather context for the U0140 code (10-15 minutes).
Step 3: Step 3: Perform component testing with a multimeter, checking the integrity of the BCM and ECM, as well as their connections (20-30 minutes)
Step 3: Perform component testing with a multimeter, checking the integrity of the BCM and ECM, as well as their connections (20-30 minutes).
Step 4: Step 4: Run a system function test to ensure all systems linked to the BCM operate correctly after any repairs and clear the codes (10-15 minutes)
Step 4: Run a system function test to ensure all systems linked to the BCM operate correctly after any repairs and clear the codes (10-15 minutes).
Step 5: Step 5: Conduct a road test to verify that the vehicle operates normally under various conditions and that the U0140 code does not reappear (15-20 minutes)
Step 5: Conduct a road test to verify that the vehicle operates normally under various conditions and that the U0140 code does not reappear (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: Repair Case: 2015 Chevrolet Malibu with U0140 Code
Vehicle: 2015 Chevrolet Malibu, 75,000 miles
Problem: Customer reported intermittent power issues with windows and doors.
Diagnosis: Upon scanning, U0140 was present along with codes for individual module failures. A visual inspection revealed frayed wires near the BCM.
Solution: Repaired the damaged wiring and reset the BCM. No further codes appeared after testing.
Cost: $150 (wiring repair plus diagnostic fee)
Result: Customer reported successful operation of all electronic systems and no recurrence of the U0140 code.
Case Study 2: Repair Case: 2014 Dodge Dart with U0140 Code
Vehicle: 2014 Dodge Dart, 50,000 miles
Problem: Customer experienced dashboard warning lights and unresponsive electronic features.
Diagnosis: U0140 was confirmed via the GeekOBD APP, and further testing indicated a faulty BCM.
Solution: Replaced the BCM and reprogrammed it to match the vehicle’s specifications.
Cost: $450 (BCM replacement and reprogramming)
Result: All features resumed normal operation, and the customer was satisfied with the repair outcome.