Quote:
Originally posted by drivesafe
Hi PCH, the CAN Bus stands for Controlled Area Network and is now an industry standard protocol or to simplify it. This is a system being employed in many new vehicles where the components literally talk to one another and the language they use is called CAN.
You will see much more of this type of electronic involvement in new vehicles because it has a whole host of advantages with probable the main one being that in the not to distant future there will only be 4 wires running around the vehicle, 2 for power and 2 for the CAN protocol.
This may sound a bit over the top but it will simplify every aspect of working on or adding to the vehicles electric's.
For example, you could buy a set of driving lights and only need to hook up 4 wires at the nearest point to where you are mounting the driving lights and again back at the dash you would fit your switch(es) and hook up to the 4 wire loop and thats it.
Both the lights and the switch would have a small microprocessor installed inside them.
The first time each device is powered up, the microprocessor in each device will tell the host computer that they are present and what they are to do.
This scenario will be common place with a large number of items that at present require lots of wiring and connecting to existing systems.
The CAN system will not only operate the additional devices but will let you know about how the devices are functioning. EG. If a driving light globe fails, you will be notified as soon as you turn on the ignition, whether you have the lights on or not.
Cheers.
Thanks Drivesafe for your explanation of the CAN BUS system. This explains to me why when I turn the ignition key to the start position the Message Centre says "System test in progress" and then chimes to tell me it has discovered an error like "Special off-road programs unavailable". The test has just discovered a system is not functional due to a loose connection or failed component. 