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Automotive Do Vehicles Use PLC's?

  1. Jun 7, 2012 #1
    My question is do vehicles use Programmable Logic Controllers?
    I ask this because I have experience on working on Mercedes and the newer model vehicles use of a part called a "SAM" there is usually a front and rear SAM, basically it is just a fuse-box but controls a lot of the cars electronics, I am wondering if this is a PLC since the main purpose of a PLC is to reduce the amount of relay's and wiring needed in a control system, even if this is not a PLC does any one know of any vehicles that do make use of PLC's for controlling vehicle electronics?
  2. jcsd
  3. Jun 7, 2012 #2
    Far as I know PLC's are used to control mechanical systems using electronic actuators. For example an EGR is controlled by a servo which determines the amount or time it needs to be opened by the emissions part of the computer.
  4. Jun 7, 2012 #3
    Modern vehicles use a network of different computer modules which are networked using CAN (closed area network). The most important module in a vehicle is the PCM (power control module), sometimes called the ECM (engine control module). Its basically the main brain of the car and does not contain a PLC or anything similar to it. It is entirely responsible for controlling the powertrain of the vehicle and its related components and is generally far more complicated for any type of PLC to handle.

    A typical modern car will have several different modules for controlling different systems and features. For example, there is a module that controls the instrument cluster, one for the sound system, one for the safety system (inertia sensor, airbags), etc. All these devices usually use some sort of microcontroller or FPGA.
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