High Speed CAN Communication Fault
There’s a problem with the high-speed CAN communication system.
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 car’s computer systems, like the engine and transmission control modules, talk to each other over a high-speed network. If there’s a fault here, it could mean loose wires or a bad module.
What the computer is actually seeing
The computer detects irregularities in the CAN network, indicating faults in communication or a missing response from a module within 5 to 100 milliseconds.
What a healthy reading looks like
CAN signal voltage should be around 2.5V (idle) and can swing between 1V and 3.5V during communication.
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 harness for damage and loose connections; repair as needed. If no issues found, move to step 2.
- 22. Use a multimeter to check the voltage levels on the CAN bus lines, aiming for 2.5V at rest. If readings are out of expected range, check for shorts or opens in wiring. If normal, move to step 3.
- 33. Monitor the CAN data using a scan tool while executing key functions to see if any modules are not responding. If a particular module fails to respond, it may need replacement. If all modules respond, consider a new code scan.
Common causes
- Loosened or corroded wiring
- Faulty connectors in the CAN circuit
- Failed control module or sensor on the bus
- Short circuit or open circuit in the wiring harness
Typical repair cost
$$
Related codes
Frequently asked questions
Can I drive the vehicle with this code?
Yes, but it’s recommended to repair it soon as it may affect other systems.
Will this code come back after I clear it?
It may return if the underlying issue isn’t fixed, especially if there are still problems with wiring or connections.
Why does this code pair with others like B2655?
They all relate to communication faults in the same network; multiple codes can indicate broader issues.
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