This guide is customized for your 2021 Honda PASSPORT
B0678: B0678: Body Control Module (BCM) Security System Malfunction
on 2021 Honda PASSPORT
Important for 2021 Honda PASSPORT Owners
Before starting repairs, verify which engine your 2021 Honda PASSPORT has. Check your VIN or engine code to ensure you order the correct parts.
📖 What Does B0678 Mean on 2021 Honda PASSPORT?
Symptoms
- • Alarm system activation
- • door locks not functioning
- • or vehicle immobilization
Common Causes
- • Faulty BCM
- • security system sensor
- • wiring issue
- • or battery voltage below 10V
How to Fix B0678 on 2021 Honda PASSPORT
1. Check BCM fuse and replace if blown. 2. Inspect and clean security system sensors. 3. Check wiring for damage or corrosion and repair as needed. 4. Update BCM software if necessary. 5. Replace BCM if faulty.
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Related Diagnostic Codes
Other codes that may appear with B0678
B0676: Seat Position Sensor Circuit Malfunction
B0677: Exterior Lighting Malfunction
B0679: Audio System Malfunction
B0680: Airbag System Malfunction
💡 Why These Codes Are Related:
- • Similar Issues: Same root cause or component failure
- • Related Problems: Often occur together due to system interactions
- • Sequential Codes: Progressive failure stages or multiple sensors
- • Same System: Components within the same automotive system