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DTC codes / U00xx · Network wiring and bus faults / U0093

U0093Vehicle Communication Bus H Performance

U0093 indicates that the vehicle's communication bus, typically the Controller Area Network (CAN) data lines, is not performing to the expected standard, meaning the modules are unable to exchange messages reliably. The computer sets this code when it detects signal degradation, such as excessive voltage drop, erratic bus levels, or missing acknowledgments, rather than a complete loss of communication.

SystemNetwork
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyProfessional
AreaNetwork wiring and bus faults

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

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