Body Control Module (BCM) Communication Malfunction
BCM is having trouble communicating with other modules.
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 Body Control Module can't talk properly with other modules in the car, which can cause malfunctions in things like lights and locks.
What the computer is actually seeing
The BCM detects a failure in the communications line or a missing signal from one of the other modules it's supposed to interface with. It expects regular signals (like voltage changes) that it's not receiving.
What a healthy reading looks like
Expected signal voltages for proper operation are typically around 2.5V to 5V for digital communications, depending on the protocol being used.
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.
- 1Check all related connectors for corrosion or loose connections; especially at the BCM and affected modules.
- 2Inspect wiring harnesses for damaged insulation or broken wires; repair any found issues.
- 3Clear the code and check for one of the codes to return.
- 4If the code comes back, test the BCM power and ground circuits; expect about 12V on power and less than 0.1 ohm on ground.
- 5If power and ground are good, try replacing the BCM if all other modules are functioning. Only replace after confirming no other issues.
Common causes
- Faulty BCM
- Wiring issues
- Bad connectors
- Faulty or disconnected module
- Intermittent short or open circuit
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but test proper functionality of key systems like lights and door locks first.
Will this problem come back after fixing it?
If it's a wiring issue or a faulty module, it might; inspect carefully.
Why does this code pair with other codes?
Multiple modules on the same communication line can cause multiple failures if one goes down.
Working a real vehicle right now?
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