Control Module Communication Fault
The control module is having issues 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 vehicle's computer can't talk properly to other computers in the system, like the ABS or transmission module.
What the computer is actually seeing
The main control module detects a lack of response or an incorrect response from another module it needs data from, which might include data on vehicle speed, wheel speed, or brake status.
What a healthy reading looks like
Communication signals between modules should be at a constant voltage of 2.5 to 5 volts; no responses or failure to meet expected data rates indicate a fault.
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. Inspect the wiring and connectors between the control modules for damage or corrosion. If any issues found, repair before proceeding.
- 22. Check the power supply to the affected modules. Ensure all related fuses are good and voltage readings are within 12-14 volts with the vehicle running.
- 33. Use a scan tool to check for any other codes that might indicate which module is causing the communication fault.
- 44. If multiple modules are involved, isolate them by disconnecting one at a time while checking for faults after each disconnection.
- 55. If a specific module is suspected, test it according to manufacturer guidelines. If it fails, replace the module.
Common causes
- Faulty wiring between modules
- Bad connector pins or corrosion
- Failing control module
- Power supply issues
- Signal interference or shorts
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's moderate; drive cautiously and fix soon to avoid further issues.
Will the code come back after clearing it?
If the underlying issue isn't fixed, it will likely return.
Why does this fault pair with C1000?
C1000 indicates a general communication error, which is often linked to module communication faults like C1070.
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