Control Module Communication Fault
There’s a problem with communication within the control 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 computer systems in the vehicle aren’t talking to each other properly, which can affect vehicle performance and operations like stability control or traction control.
What the computer is actually seeing
The control module detects an interruption or failure in the communication channels between itself and other modules, usually sending a voltage signal that’s out of expected ranges or a system timeout.
What a healthy reading looks like
Communication signals should fluctuate between 0.5V to 12V depending on the module state and should respond within 250ms.
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 for any visible damage to wiring harnesses and connectors related to the modules involved. Repair any issues found.
- 22. Verify that the battery voltage is between 12.4V and 14.8V with the vehicle running. Low voltage can cause communication failures.
- 33. Use a multimeter to check signal voltages on the communication lines between modules. Look for expected voltage ranges.
- 44. Inspect for any TSBs related to software updates for the control modules. Update software if available.
- 55. If communications appear fine, swap the suspect control module with a known good one, and see if the code clears.
Common causes
- Damaged wiring or connectors
- Faulty control module(s)
- Software glitches or corruption
- Corrosion at the communication terminals
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but you may experience issues with traction control or stability control systems.
Will this code come back after clearing it?
It may return if the underlying issue isn’t resolved, typically due to a wiring fault or faulty module.
Why does this code often pair with other codes?
Multiple codes can indicate that several modules are affected by the same communication fault, often due to a common wiring problem.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
Start guided diagnostic →