Malfunction Indicator Lamp: Description and Operation

SERVICE VEHICLE SOON
The Instrument Panel Cluster (IPC) illuminates the SERVICE VEHICLE SOON message in the message center when any of the following conditions occur:
The Powertrain Control Module (PCM) detects certain malfunctions that are not related to the emissions system. The IPC receives a class 2 message requesting illumination from the PCM.
The IPC detects a loss of class 2 communication with the PCM.
The IPC does not detect any class 2 communication with the vehicle.