CAN BUS Functional Diagram

CAN BUS FUNCTIONAL DIAGRAM





FLEXIBLE SERVICE SYSTEM (FSS) INDICATOR





The Flexible Service System (FSS) indicator (2) draws the attention of the driver to a particular service that is due. The FSS indicator (2) is a mileage/time-activated engine service system for recommended oil change intervals. In addition to time (in days) and distance criteria, other factors, such as extreme speeds or cold starts that are in combination with short distances, are taken into account for adjusting the programmed service intervals. If the oil level drops below a warning threshold, the remaining distance (1) or the remaining time (1) and the tool symbol (2) are displayed. The FSS indicator (2) has its own microprocessor in the Instrument Cluster. The FSS indicator (2) obtains time information from the digital clock integrated into the Instrument Cluster. The other data required is obtained via the CAN data bus from the Controller Antilock Brake (CAB) and the Powertrain Control Module (PCM).

The following are CAN Bus data inputs required for FSS indicator operation:
- CAB supplied input: 4 wheel speed signals for calculating vehicle speed
- CAB supplied input: 4 wheel speed signals for calculating distance traveled
- PCM supplied input: Engine coolant temperature
- PCM supplied input: Engine speed
- PCM supplied input: Engine load