Brief Description
P-BUS AND I-BUS
A smaller number of control modules in the Saab 9-3 are connected to the bus system compared with the Saab 9-5.
The two power train systems EDC and diesel pump are not connected to the I-bus. These systems require much faster communication so that no discernible delays occur, e.g. when EDC requests a certain amount of fuel for injection.
Therefore, they are connected to a separate bus called the P-bus (Powertrain Bus). The P-bus communicates ten times faster than the I-bus.
In addition, the P-bus is also connected to the MIU (the main instrument display panel). The MIU is responsible for making the information available on one bus also available on the other bus.