What it means
Intermittent dropouts or noise on input power line C. A communication loss with this module breaks any function relying on its data — diagnostic tools may show 'no response' and dependent modules can fall into limp mode.
At a glance
- Usually lights the warning light of the system that lost communication
How it works
The module monitors its C input-power feed for interruptions or unstable readings. This code sets when voltage on the C feed drops out or fluctuates, which can interrupt module operation or communication.
Common causes
Most likely first.
- Connector loose or corroded
- Gateway module routing CAN messages incorrectly
- CAN terminating resistor (120 Ω) drifted out of spec
Symptoms
- Multiple warning lights may illuminate
- Affected modules may go into limp mode or shut down
- Specific functions inoperative depending on module
- Diagnostic tools may show communication faults
How to diagnose it
- Save freeze-frame data and scan all modules for matching communication or voltage faults to identify when the C-feed interruption happened.
- Inspect the module’s C-feed connector, fuse, wiring, and ground for looseness, corrosion, chafing, or heat damage.
- Monitor C-feed voltage while gently moving the accessible harness and connector to reveal intermittent contact.
- Check voltage drop through the C supply and ground under the manufacturer's specified test conditions.
- If the C supply remains stable, use the wiring diagram to inspect gateway routing and test CAN wiring and termination.
Common fixes
- Clean and secure the C-feed connector or ground.
- Repair chafed, broken, or high-resistance C-feed wiring.
- Replace a damaged fuse terminal or connector pin.
- Repair a confirmed gateway or CAN termination fault if the C-feed supply is stable.
Can I keep driving?
If the module or a dependent safety or drivability function cuts out, stop safely and arrange diagnosis because an intermittent supply can become a complete failure. If only noncritical functions are affected, limit driving and avoid relying on functions that are dropping out.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.