A VEHICLE SAFETY ELECTRONIC CONTROL SYSTEM

There is disclosed a vehicle safety electronic control system (8) comprising a first microcontroller (11), a second microcontroller (12), and an inter-processor communication path (13) for bi-directional transfer of data between said microcontrollers (11,12). The system has a first mode of inter-processor communication in which said first microcontroller (11) acts as a master and said second microcontroller (12) acts as a slave, and a second mode of inter-processor communication in which said second microcontroller (12) acts as a master and said first microcontroller (11) acts as a slave. Mode selection means (18-20) is provided to select and switch between said first and second modes.