FMI 19 — Received network data in error
The message arrived over J1939 but its contents were invalid. This points at the sending module or the bus, not at a sensor.
Common causes
- Faulty source module
- Bus noise or wiring fault
- Mismatched module software versions
- Aftermarket device flooding the bus
What to test, in order
- Identify which module owns that SPN and check its own codes first
- Check bus health: 60 ohms key-off, clean backbone connectors
- Disconnect aftermarket telematics and retest
- Compare module software levels against the OEM build
Codes we document with FMI 19
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