General

General
The vehicle's electrical system consist of a number of control modules on the CAN and MOST network. The functions of the vehicle can be divided between the different control modules in the vehicle. The vehicle's different functions are implemented via the CAN and MOST network. Each control module is loaded with software that executes functions and monitors the control module through integrated diagnostics.

Incorrect or failed functions in the vehicle usually depend on hardware faults, for example, contact play, oxidation, breakages or short-circuiting.

Software is not worn out and its function is not impaired overtime, however, unforeseeable behavior can occur in software which means it needs to be upgraded. It may also be necessary to upgrade software on account of legislation or when moving to another market.

When starting the control module the primary bootloader starts (PBL) for 20 ms (0.02 seconds). Should the control module receive a programming command (prog) during these 20 ms the control module enters programming mode.

The programming command is sent for approximately 2 seconds so that all control modules have time to execute the command and enter programming mode. If no programming command is sent the control module's application software takes over the function of the control module.

If a reset command is sent to the control modules in programming mode, the control modules will enter normal operating mode.

The primary bootloader means it is always possible for a control module to enter programming mode even if the application software has been corrupted, for example, during unsuccessful downloading.