Data Link Communication Issue
There's a problem with data communication on the vehicle's network.
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 is having trouble talking to other computers or modules, which can disrupt engine performance or safety features.
What the computer is actually seeing
The Engine Control Module (ECM) detects a communication failure on the CAN bus, meaning it's not receiving or sending the correct data packets within a specific timeframe.
What a healthy reading looks like
The expected CAN data packets should be transmitted every 10 milliseconds; if a packet is missed or delayed by more than 50 milliseconds, the fault may trigger.
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. Start with a visual inspection of all CAN bus wiring and connectors; look for signs of damage or corrosion. Decision: If you find damage, repair it and retest; if not, continue.
- 22. Use a digital multimeter to check the voltage on the CAN high and CAN low wires. Expect around 2.5V at rest and 3.5-5V when active. Decision: If voltages are out of range, repair wiring; if okay, proceed.
- 33. Check for any other active fault codes that may provide additional context; they could point to the root cause. Decision: If related codes exist, focus on those; if none, continue.
- 44. Disconnect modules one at a time (like ABS, transmission, etc.) and see if the fault clears, indicating a specific module issue. Decision: If fault clears with a module disconnected, focus on that module for issues; if not, proceed to the next step.
- 55. Inspect and test any aftermarket devices connected to the CAN network; they may be creating interference. Decision: Disconnect them and see if the error returns.
Common causes
- Faulty wiring or connectors in the CAN bus system
- Failed or malfunctioning ECM or other control modules
- Electrical interference from aftermarket devices or poor grounding
Typical repair cost
$$$
Related codes
Frequently asked questions
Can I still drive with this code?
Yes, but you may experience performance issues or lose functionality of certain systems.
Will this code come back after clearing?
It can if the underlying issue isn't resolved.
What happens if I ignore it?
Ignoring this code can lead to further communication issues and may affect engine performance or safety features.
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 →