Body Control Module - Communication Error
The Body Control Module (BCM) can't communicate with the network system.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The vehicle's Body Control Module, which manages various electronic systems like lights and locks, isn't talking properly with the other modules, likely due to a wiring problem or a bad connector.
What the computer is actually seeing
BCM sees no response from the other modules within the network when it tries to communicate. This could mean voltages are out of expected range (below 0.5V) when they should be around 2.5V during communication checks.
What a healthy reading looks like
Communication lines should have a voltage around 2.5V to 5.0V while operating.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check all wiring and connectors to the Body Control Module for damage or corrosion.
- 22. Use a multimeter to measure the voltage on the communication lines; expect 2.5V - 5.0V. Are the voltages correct?
- 33. If voltages are correct, test for communication with a scan tool; can you connect to the BCM?
- 44. If you can't connect, disconnect other modules from the network one at a time and test communication. Did that restore communication?
- 55. If still no communication, consider replacing the BCM as a last resort.
Common causes
- Damaged wiring harness
- Corroded connectors
- Faulty Body Control Module (BCM)
- Issues with a connected module
- Battery voltage issues
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It might run without major issues, but you could lose control of certain electronic functions like lights and locks.
Will this code come back after clearing?
Yes, if the underlying issue isn't fixed, it typically will return.
Why does this code pair with B101D?
Both are communication errors related to the Body Control Module and other modules in the network may be experiencing similar issues.
Working a real vehicle right now?
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