Quick Answer
B1691 means: B1691 indicates a problem with the body control module, affecting various electronic systems in your vehicle.
Can I drive with B1691? Immediate attention is recommended to prevent further electrical issues.
Common Questions
What does B1691 mean and how does it affect my car?
B1691 indicates a communication issue within the body control module, affecting various electronic systems such as lights and power accessories. If ignored, it may lead to increased electrical drain or failure of these components.
What are the most common causes of B1691 and how much does it cost to fix?
Common causes include faulty BCM connections (60%), a malfunctioning BCM, electrical shorts, and wiring issues. Repair costs can range from $150 for wiring repairs to $800 for BCM replacement.
Can I drive my car with B1691 or should I stop immediately?
While you may be able to drive your vehicle, it is advisable to address the B1691 code promptly to avoid further electrical issues that could lead to breakdowns or safety risks.
How can I diagnose B1691 myself using GeekOBD APP?
Download the GeekOBD APP, connect it to your vehicle's OBD2 port, and use it to read diagnostic codes. Look for B1691 and any related codes, then analyze the freeze frame data for context.
What vehicles are most commonly affected by B1691?
The B1691 code is frequently seen in 2012-2017 Honda Civics and 2013-2019 Toyota RAV4s, among others. Check for any recalls or technical service bulletins related to these models.
How can I prevent B1691 from happening again?
Regularly inspect your vehicle’s wiring and electrical components for signs of wear, and ensure proper maintenance of the body control module and related systems.
What is B1691?
The B1691 diagnostic trouble code refers to an issue within the body control module (BCM) of your vehicle, specifically indicating that the BCM has detected a fault in the communication or functionality of its systems. This code is commonly seen in vehicles from manufacturers like Honda and Toyota, especially in models like the 2012-2017 Honda Civic and the 2013-2019 Toyota RAV4. When the B1691 code is triggered, it typically means that there is a problem with the vehicle's electrical system, which can lead to issues such as malfunctioning lights, power windows, and other electronic components. The BCM is responsible for managing various functions within your vehicle, including lighting, security features, and interior climate control. If left unresolved, a B1691 code can lead to further complications, such as increased electrical drain on the battery, potentially causing the vehicle to fail to start or lead to intermittent failures of other electronic systems. Therefore, addressing this code promptly is crucial for maintaining your vehicle's electrical health and overall functionality.
System: B - Body (Airbags, Lighting, Security, Climate Control)
Symptoms
Common symptoms when B1691 is present:
- The check engine light is illuminated, indicating that the vehicle's computer has detected a fault.
- Power windows may not function properly, with some windows failing to open or close as expected.
- Interior lights flicker or do not turn on, which can indicate issues with the BCM's control over the vehicle's lighting systems.
- The vehicle may experience intermittent starting issues, where the engine fails to crank or starts inconsistently due to electrical drain.
- Security system malfunctions, such as key fob not working or alarm activating unexpectedly.
Possible Causes
Most common causes of B1691 (ordered by frequency):
- The most common cause of the B1691 code is a faulty body control module connection, accounting for approximately 60% of cases. This can be due to loose connectors or corroded wires that disrupt communication between the BCM and other systems.
- Another common issue is a malfunctioning BCM itself, which can result from software glitches or hardware failures. This technical problem might require reprogramming or replacement of the module, particularly if the vehicle is older.
- Electrical shorts in wiring harnesses can also trigger B1691. To prevent this, regular inspections of the vehicle's wiring system are advised, especially in areas prone to wear and tear.
- Less common but serious issues include water damage to the BCM, which can occur if the vehicle has been involved in flooding or if seals are damaged, allowing moisture to enter critical electronic components.
- A rare cause could be a failed fuse associated with the BCM. Fuses are easy to check and replace, but overlooking this simple solution can lead to more complex repairs.
B1691 Repair Costs
Cost Breakdown by Repair Type
BCM Replacement
Replacing the faulty body control module with a new or refurbished unit.
- Total: $400 - $800
- Success rate: 85%
Wiring Repair
Repairing or replacing damaged wiring or connectors leading to the BCM.
- Total: $150 - $300
- Success rate: 90%
Software Reprogramming
Reprogramming the existing BCM to resolve software-related issues.
- Total: $100 - $200
- Success rate: 70%
Money-Saving Tips for B1691
- 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 B1691 Diagnosis Process
Follow these systematic steps to accurately diagnose B1691. Each step builds on the previous one to ensure accurate diagnosis.
Step 1: Perform an initial visual inspection to check for obvious signs of damage, such as frayed wiring, loose connectors, or corrosion around the BCM (5-10 minutes)
Step 2: Use an OBD2 scanner or the GeekOBD APP to retrieve all stored codes and freeze frame data, allowing you to understand the context of the fault (10-15 minutes)
Step 3: Conduct component testing using a multimeter or dedicated diagnostic tools to check voltage and continuity at the BCM and related circuits (20-30 minutes)
Step 4: After repairs, perform a system function test to verify that all components are operating correctly and clear any diagnostic codes (10-15 minutes)
Step 5: Conduct a road test to evaluate the vehicle under various conditions, ensuring that all systems are functioning normally post-repair (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: BCM Replacement in a 2015 Honda Civic
Vehicle: 2015 Honda Civic, 60,000 miles
Problem: Customer reported intermittent power window failure and flickering interior lights.
Diagnosis: Diagnostic scan revealed B1691 and confirmed wiring issues along with a faulty BCM.
Solution: Replaced the BCM and repaired damaged wiring.
Cost: $600 (parts: $450 for BCM, $150 for wiring repair)
Result: Customer reported all systems functioning normally after repair.
Case Study 2: Wiring Repair in a 2018 Toyota RAV4
Vehicle: 2018 Toyota RAV4, 30,000 miles
Problem: Vehicle experienced erratic lighting and starting issues.
Diagnosis: B1691 was detected; inspection found corroded connectors.
Solution: Replaced corroded connectors and cleaned the wiring harness.
Cost: $200 (parts: $50 for connectors, $150 for labor)
Result: All issues resolved; vehicle performance returned to normal.