Automotive question

Thread Starter


Joined Sep 16, 2008
I know that the auto industry is working on a plan to run our cars with, essentially, a two wire harness. (I am primarily talking about the lighting system here).

In this system, there will be a power wire and a serial data line. At every light socket in the car, the light will be controlled by a small chip in the socket that gets its instructions from the data line.

No more wires for stop, turn, tail, etc. Just two wires to virtually every bulb in the car! I have a 2005 Chrysler Crossfire Roadster (the most fun vehicle on the road, but that is beside the point) - the newest vehicle I'v owned and it is NOT wired like this. A co-worker's new car is a 2008 and IT is not wired like this, either.

MY QUESTION: Do any of you here know of a car that is already wired like this?

My bet is that it is STILL in the future... what say the contributors here?


Joined Oct 17, 2009
alot of cars are already like this.

I used to work at BMW's Quality and Engineering Centre. The car is full of ECU (electronic control units), which speak to each other using data lines such CAN bus, K lines, etc. They are usually daisy chained to one another, so the same wires that would display info the dashboard could also trasmit data to the body control ECU to open the windows. The only real exception is for the airbags where it has it's own unique data lines.

CAN bus tends to be of the twisted pair type.

MINI and all of the BMW range use this type of system.

On the plus side it makes diagnosis much much easier, as everything is logged onto ECU and any problems are logged as fault codes, which can tell anything from what speeds you were doing when you crashed the car to what is causing the misfire on the engine.


Joined Oct 17, 2009
there is still a big wiring harness going around the car to the various components, such as tail lights, fans, windows, etc. Just everything isn't controlled directly by a switch anymore. Operating the window switch sends a signal to the body control unit to make the choice whether the window motor is actuated.