Body Control Module (BCM) - Unauthorized Access
The Body Control Module has detected unauthorized access or tampering.
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 car's computer is seeing signs that someone tried to get into the system without permission, like a key or fob that doesn’t belong to the car.
What the computer is actually seeing
The BCM monitors inputs from security features. When it detects a mismatch or unauthorized attempt, it sets this code along with monitoring voltage levels or signals from the key fob.
What a healthy reading looks like
Key fob battery should be near 3V; BCM input signal should confirm correct fob identity within 20-30 ms after pressing the button.
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 battery voltage; it should be above 12.0V. If below, charge or replace the battery.
- 2Inspect wiring and connectors related to the BCM for signs of damage or corrosion. Repair as needed.
- 3Test the key fob battery; it should be around 3V. Replace if low or dead.
- 4Use a scan tool to check for additional codes or history that may indicate a common issue.
- 5Clear the code and see if it returns after a normal operation cycle.
Common causes
- Faulty key fob
- Damaged wiring or connectors to the BCM
- Software glitch in the Body Control Module
- Battery voltage below 12.0V affecting security systems
Typical repair cost
$$-$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
While you may still be able to drive the vehicle, it’s recommended to fix this to avoid potential issues with starting or security features.
Will this code come back after clearing the PCM?
If the underlying issue isn’t resolved, the code is likely to return after normal use.
Why does this code pair with other BCM codes?
BCM codes often reflect issues with security systems that are interconnected; one problem can trigger multiple related codes.
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