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Diagnostics of systems of electronic control and diagnostic equipment
general information System of onboard self-diagnostics The composition of the OBD system includes several diagnostic devices making monitoring of separate parametres of systems of decrease in toxicity and fixing revealed refusals in memory of the onboard processor in the form of individual codes of malfunctions. The system also produces verification of sensors and actuators, controls the cycles of vehicle maintenance, allows storing even briefly encountered in the process crashes and cleaning of the storage unit. All are described in this manual model equipped with second-generation on-board diagnostics (OBD II), the main element is the onboard processor, more often referred to as electronic control module (ECM - on), or (less often) the operation of the control unit of the power unit (PCM). ECM is the brain of the engine management system. Input data is input to the information from various sensors and other electronic components (circuit breakers, relays, etc.). Based on the analysis coming from information gauges the data and in accordance with laid down in the memory of the processor basic parameters, ECM generates commands to trigger various control relays and actuators, thereby effecting adjustment of the operating parameters of the engine and providing peak efficiency of its return at the minimum fuel consumption . Arrangement of electronic control modules for various vehicle systems is shown in the illustration details the installation Control Module front door. Reading the data processor memory OBD II (ECM) is made using a special scanner connected to a 16-pin diagnostic socket reader Database (DLC). Using the same scanner is carried out and cleaning the processor memory. Running the DTC procedures for reading and cleaning ECM memory is wise to instruct the service specialist.  | On some models, reading the stored ECM fault codes (DTC) can in principle be produced with the help of auxiliary LEDs, as well as the codes displayed on the display automatically K / V. |
DLC connector is placed to the left under the dashboard of the car
Identification of terminals 16-pin diagnostic connector (DLC) Data on diagnostic devices Connection of a multimeter to the connectors of the control unit by means of an auxiliary engine coupler  Check of serviceability of functioning of components of systems of injection and emission control is performed with a universal digital meter (DMM). Using a digital meter is preferred for several reasons. First, on analogue devices it is difficult enough (at times - impossible) to determine the result of readings with an accuracy of hundredths and thousandths, while at inspection of the contours including in the structure electronic components, such accuracy takes on special significance. The second, no less important reason is the fact that the internal contour of a digital multimeter, has high enough impedance (internal resistance of the device is 10 milliohms). As the voltmeter is connected to a checked chain in parallel, accuracy of measurement is higher, the less current will flow through the device itself. This factor is not significant when measuring relatively high voltages (9 ÷ 12), but becomes the determining the diagnosis of issuing low voltage components, such as, for example, lambda probe, which refers to the measurement of a volt. Parallel monitoring of signal parameters, resistance and voltage in all control circuits possible using a splitter connected in series to the engine control unit connector. Thus on the switched off, the engine is running or while the vehicle is moving, the signal parameters are measured at the terminals of the hub, from which a conclusion about possible defects. For the diagnosis of the electronic systems of the engine, automatic transmission, ABS, SRS and others can use special diagnostic scanners or testers with a certain cartridge (if provided), a universal cable and connector. In addition, for this purpose, you can use expensive specialized automobile diagnostic computer specially developed for full diagnostics of the majority of systems of modern cars (for example, ADC2000 firms Launch HiTech). Also, for this purpose can apply scanners and specialized diagnostic analyzers, such as FDS 2000, Bosch FSA 560 (www.bosch.de), KTS500 (0684400500) or a conventional personal computer with a special adapter cable (eg, a set of 1687 001 439) and the established program browser OBD II. | The free version of browser OBD II for diagnostics of your car, you can also download the drafters of this Guide http // arus.spb.ru. |
Some scanners, besides usual operations of diagnostics, allow, when connecting to a personal computer to print data stored in the control unit electrical circuit diagrams (if incorporated), anti-theft system to program, monitor signals in the circuits of the vehicle in real time. Reading of diagnostic codes and clearing processor memory Wiring reader STAR DIAGNOSIS (0100) to the diagnostic socket DLC (X11 / 4)  Read the DTC and clearing processor memory board self-diagnostic system is carried out using proprietary scanner STAR DIAGNOSIS (0100) connected to the 38-pin DLC (X11 / 4) of the car. By connecting the reader to the socket DLC, switch on the ignition and start the driver authorization system (DAS). The menu ?�MODEL DESIGNATION?� Reader, click ?�FIRTHER MODEL SERIES?�, then proceed in accordance with the instructions on the screen, depending on the task (code reading, garbage collection and so forth.).
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