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Automotive Computer Modules - general knowledge

The automotive onboard computer modules is a very complex device that is programmed to control and monitor specific aspects of a specific automobile. The ECM is the most referred to but it is not the only onboard. For example the 2014 Lincoln MX has 39 (and this car these modules all collaborate with each other the control the operation of the car and they do so wireless. Consider this when contemplating working or replacing one.
1. You may think it is the ECM, but it could be one of the modules giving the ECM false data. Alright - which one do you replace or fix. Unless you have had the problem specifically diagnosed that it is a specific module that has failed or is ailing (short of a module having been physically damaged, you won't know.
2. If you go out an acquire another module it is going to be flashed (clear it and reload a new set of program instructions). (the module is costly to acquire - even from a wrecker)
3. In order to flash the module you first need the "program Instructions" from the manufacturer. (usually their database and you need access to that - that is costly.
4. Then you need the computer gear from the manufacturer - to hook up to the car in order to carry out the flash. (another costly item)
5. You are far better spending your money at the dealer or a shop with the correct equipment.Spend the couple hundred bucks and send it to either a dealer, a shop that has the equipment, or a mobile service company that specializes in flashing modules. (you need to flash the one that is failing or failed or the newly acquired one)

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Automotive vehicles are increasingly being equipped with collision avoidance and warning systems for predicting the potential collision with an external object, such as another vehicle or a pedestrian. Upon detecting a potential collision, such systems typically initiate an action to avoid the collision and/or provide a warning to the vehicle operator. The aim is to design and develop a control system based on an automatic, intelligent and electronically controlled automotive braking system for automobiles is called as "INTELLIGET BRAKING SYSTEM". This Braking system consists of IR transmitter and receiver circuit and the vehicle. The IR sensor is used to detect the obstacle. There is any obstacle in the path, the IR sensor senses the obstacle and giving the control signal to the microcontroller, which in turn sends a signal to the motor to stop and also to the solenoid so as to stop the vehicle as programmed. This project facilitates electromagnetic braking system using solenoid. Here in fabrication module include a circular disc associated with a dc motor and a solenoid. Embedded system module includes micro controller with a solenoid and sensor

Dec 17, 2016 | Ford Cars & Trucks

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What and where is the body control module on a 2004 kia spectra

I sorry Girl but if you have to ask what it is I suggest you take your vehicle to a ASE certified repair shop or the dealer . Automotive electronic control modules are very complex .

Jan 07, 2016 | Kia Cars & Trucks

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  • A B.C.M. is................
    A body control module is a computer component in an automobile that checks, regulates and operates electronic devices throughout the car. When electric devices first began being used in cars and trucks, each device was governed by a separate electric component. There was a module for the air-conditioning, a module for the interior lighting, a module for the door locks, and so forth. A body control module gathers all these separate modules under one system so that they function together instead of separately, a format easier to both manufacture and troubleshoot.
  • While there are many different types of body control modules, they are generally alike, connecting sensors, switches and automatic reactions together in one computer system. These components are divided into inputs, such as sensor data about heat or speed, and outputs, or ways in which the body control module computer responds to control the vehicle's electronic functions. Inputs and outputs are further divided into analog and digital types of information--analog signals being used with modules that may change continuously (such as oil pressure) and digital signals being used for modules that can simply be on or off (like the headlights or the oil indication light).
Inputs and Outputs
  • Input components are divided into electric parts, such as the potentiometer, the variable resistor, the magnetic pickup and the voltage generator. A potentiometer is designed to change a voltage output to the computer, so that when a fuel setting or gas-pedal position is changed, the voltage will change and the computer will read the new voltage and respond accordingly. The variable resistor works in a similar fashion, but senses changes in temperature for reading engine coolant conditions and other data. The magnetic pickup reads the speed of a rotating object via a simple magnet attached to the object, and a voltage generator sends out a voltage signal based on the presence of compounds like oxygen so the computer can tell the oxygen-rich levels of a pipe or space.
    Output devices consist of relays, solenoids, servomotors, switching transistors and others. Relays can turn other devices on and off by connecting or disrupting a circuit to turn on a fan or automatic air conditioning unit. Solenoids are analog components that use magnetic forces to move objects, such as fuel injectors. A servometer is a mini-motor also used to move objects, usually to turn things, while a switching transistor is the digital version of a relay. Other output devices can be very simple, such as LED lights, or very complex, such as a night-vision view of the road.
Computer Tasks
  • The body control module computer performs many of the functions of a normal computer, including storing data, using RAM and sending or receiving radio waves. The computer regulates many of the systems and troubleshoots all its component modules. Some modules are set by timer, which the computer digitally keeps track of, while other modules--like the anti-theft alarm--need to be active even when the car is turned off. The body control module computer also can be in charge of keeping track of mileage and CO2 output.
    When troubleshooting, a mechanic often is pointed to the right area by the body control module system, which sends out a code that shows what module is not responding. At times, the body control module computer can diagnose itself and report specific problems.

Oct 26, 2012 | 2004 Dodge Grand Caravan

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what a body control modual

a body control module is a computer component in an automobile that checks, regulates and operates electronic devices throughout the car. There was a module for the air-conditioning, a module for the interior lighting, a module for the door locks, and so forth. A body control module gathers all these separate modules under one system so that they function together instead of separately, its easier for the manufacturer and to troubleshoot. good-day !

Apr 09, 2012 | Cars & Trucks

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I have 2002 pontiac grand am 2.2 liter. Car shut off while driving. It cranks over fine. Won't start due to no spark. Changed ignition control module crankshaft sensor and Coil packs still no cigar? No spark??

wow, you changed the ignition control module, crank sensor, and coil packs and no spark?

Take to an auto electric shop where they can test the wiring to see if there are any breaks between the sensors or parts you already invested in.

Can your scanner communicate with the PCM?
Powertrain Control Module (PCM) Operation The OBD 2 Engine Management System (EMS) computer can be a single computer comprised of several solid-state components or a multi-microcomputer device. This computer controls the functions of the EMS and performs OBD 2 diagnostic routines. These two distinct portions of the OBD 2 EMS computer function, in conjunction, with each other. The computer architecture and software design allows the OBD 2 EMS computer to adapt its operating strategies to a variety of conditions to optimize the EMS. Federal guidelines require the EMS OBD 2 computer to continuously monitor the operating conditions of the EMS. It must also record and report any system or component failure that may cause tailpipe emissions to exceed typically 1-½ times the federal test procedure.
The OBD 2 EMS computer is specifically designed to perform powertrain system management and monitoring. Regardless of the manufacturers design and implementation of operating strategies, all computers are designed and built following the same basic considerations.
All computers contain one or more microprocessor. Microprocessors are constructed of a complex arrangement of digital circuits. One microprocessor may contain upwards of 250,000 logic circuits. These are housed in a silicon-based integrated circuit (IC) no bigger than an area of approximately ¼ inch square. The microprocessor cannot perform calculations and decisions without instructions that are programmed into the computer’s memories.
IC Micro Processor One single microprocessor, called the Central Processing Unit (CPU), is dedicated to maintaining control over the entire computer. The CPU performs all of the calculations and logical decisions. Operating instructions for the CPU are preprogrammed into other memory locations and are ‘read-only’ programs. These programs are permanent and generally cannot be altered by service personnel in the field.
A program, in general, is a set of instructions arranged in a specific order to accomplish a specific task. Each instruction in the program is assigned to a specific location, or address within the computer’s memory. Only the address of where the instruction is stored is retained in the CPU. When the CPU requires information to perform a calculation, it looks for the address of the required data and then copies the data from the memory location. This copy is retrieved and temporarily retained by the CPU for processing. Retrieving programs in this manner ensures that the information programmed in memory is retained and does not change.
The following symptoms can be caused by an open, short to ground, short to power or excessive resistance in the power and ground circuits, data line communication malfunctions and /or component failure.
Related Symptoms
  • No Crank
  • No Start condition
  • No communication with scan tools
  • No communications with other modules
  • MIL lamp illumination
  • Intermittent component functions
  • Poor fuel economy
  • High emissions
  • Drivability concerns (stalling, bucking, stumble etc.)
  • Charging system malfunctions

Jun 26, 2010 | 2002 Pontiac Grand Am

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