All trouble codes → Lost communication (CAN bus) codes
Lost communication (CAN bus) codes
“Lost communication” codes mean one module can no longer hear another on the CAN bus. A module's power or ground, damaged bus wiring or a connector, a failed module, or low battery voltage during cranking are the usual causes. A full module scan showing which modules are missing, plus a resistance check across the bus, narrows it down fast.
Network/communication fault — related systems may misbehave. Check power, ground and connectors of the module named.
Common causes
- Module power or ground supply
- Damaged CAN wiring or connector
- Failed module
- Low battery voltage during cranking
First checks
- Run a full module scan — which modules are missing?
- Check battery voltage and the fuses feeding the module
- Measure CAN-H/CAN-L resistance at the DLC (about 60 Ω with everything connected)
System: Network communication. This is general guidance for the generic OBD-II codes in this group; always confirm against the service information for your specific vehicle.
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