Bxxxx · Body
B1000
ECU Malfunction (BCM Internal)
CriticalBody ECU
What it means
The Body Control Module has detected an internal fault. May affect lighting, locks, wipers, or other body functions depending on the vehicle.
Common causes
Listed in rough order of frequency. Verify with vehicle-specific service info before parts replacement.
- 01Internal BCM hardware failure
- 02Water intrusion into the BCM (common on flooded vehicles)
- 03Failed BCM power supply or ground
- 04Recent battery disconnect or jump start
- 05Corrupted BCM configuration data
Affected systems
ECUs and subsystems that report or are affected by this code.
Body Control Module (BCM)
Get vehicle-specific diagnosis for B1000
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Ask the forums about B1000Critical-severity code
This code typically prevents the vehicle from starting, running normally, or operating safely. Diagnose carefully before clearing — clearing without fixing the root cause often masks deeper problems.