U0479 indicates that the Powertrain Control Module (PCM) has received data from a restraint system sensor that is out of range or otherwise invalid. This typically relates to the occupant classification or airbag restraint sensors.
The occupant classification sensor, seat belt buckle sensor, or crash sensor is providing out‑of‑range voltage or signal.
Corroded pins, broken wires, or loose connectors in the sensor circuit can corrupt the data sent to the PCM.
Insufficient voltage or a bad ground reference can cause the PCM to read invalid data.
A rare internal fault in the PCM’s SRS communication module may misinterpret valid data as invalid.
In most cases no. The PCM is rarely the cause; sensor or wiring problems are far more common. Replace the PCM only after all sensor and circuit checks have been exhausted.
Clearing the code may turn off the warning light temporarily, but if the underlying sensor or wiring issue remains, the code will return.
When the PCM flags invalid data, it may disable the airbag or place it in a reduced‑function mode. The vehicle should be inspected and repaired before driving.
Yes. The buckle includes a sensor that reports occupant presence; a fault there can produce an invalid‑data condition.