Data Link Error
Communication issue between controllers in 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 can't talk to another computer, usually due to bad wiring or connections between them, which can lead to performance issues.
What the computer is actually seeing
The engine control module (ECM) detects that another module (like the transmission control module) isn't responding or sending expected signals on the data bus.
What a healthy reading looks like
The data bus should have voltages typically around 2.5V (idle) to 3.5V (active communication) depending on the communication protocol in use.
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 the physical condition of wiring and connectors for damage.
- 22. Verify power and ground to the affected modules (refer to wiring diagram). Expect 12V for power and close to 0V for ground.
- 33. Inspect for resistance on the data bus, should be near 60 ohms.
- 44. Use a diagnostic scanner to check if other related fault codes are present. This can indicate a broader communication issue.
- 55. If possible, perform a continuity test on the data line between the modules. Expected continuity without significant resistance.
Common causes
- Faulty wiring or connectors on the data link
- Failed control module (like ECM or TCM)
- Bad ground or power supply to module
- Corrosion or mechanical damage in connector pins
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Driving might be possible, but communication issues can lead to loss of control features, so fix it soon.
Will this problem come back after I clear the code?
If the underlying issue isn't fixed, it likely will return.
Why does this code appear with other codes?
Multiple codes indicate that other systems may also be experiencing communication issues.
Working a real vehicle right now?
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