Data Link - Data Transmission Issue
There is a problem with data communication over the CAN bus.
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)
Your vehicle's computer can't talk properly with other systems because of a communication breakdown.
What the computer is actually seeing
The onboard computer detects inconsistent or missing data packets from another module on the CAN bus network, which should be updating frequently, typically every 10-50 ms depending on the system.
What a healthy reading looks like
Expected data packets are sent every 10-50 ms; voltage levels on the CAN High and CAN Low lines should be between 2.5V-3.5V during communication; errors detected in transmission timing.
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 associated with the CAN bus for corrosion or damage.
- 22. Measure the voltage on the CAN High and CAN Low lines. Must be between 2.5V-3.5V. If not, repair wiring as needed.
- 33. Check for additional fault codes that may indicate which module is having issues.
- 44. If no faults are found, consider testing or replacing the suspect control module that isn't communicating properly.
Common causes
- Loose or corroded connectors on the data link
- Faulty wiring in the CAN network
- Malfunctioning or unresponsive control module
- Interference from other electrical components
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's generally not safe, as it may affect essential systems. Drive cautiously and get it checked soon.
Will this code come back after repairs?
If the underlying issue is fixed, the code shouldn't reappear. However, if the fix is temporary, it may return.
Why does this code sometimes pair with SPN 5602?
SPN 5602 indicates a specific issue with another module that is often related to the overall data link function.
Working a real vehicle right now?
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