Table of contents: On-board diagnostic system (OBD) ↓ Information about diagnostic tools ↓
On-board diagnostic system (OBD)
1. The models described in this manual are equipped with the European On-Board Diagnostics (EOBD) system.
2. Reading OBD system data and clearing the processor memory is performed using special diagnostic equipment connected to the diagnostic connector (DLC), located on the left under the steering column - see illustration.
4.2. Diagnostic connector.
It would be wise to entrust the procedures of reading/erasing DTC codes and clearing the ECM memory to service station specialists.
Information about diagnostic tools
3. Checking the proper functioning of the injection system components and reducing exhaust toxicity is carried out using a universal digital meter (multimeter). Using a digital meter is preferable for several reasons. Firstly, it is quite difficult to use analog instruments (sometimes it's impossible), determine the reading result with an accuracy of hundredths and thousandths, while when examining circuits that include electronic components, such accuracy becomes especially important. The second, no less important, reason is the fact that the internal circuit of the digital multimeter has a fairly high impedance. Since the voltmeter is connected in parallel to the circuit being tested, the lower the current that passes through the device itself, the higher the measurement accuracy. This factor is not significant when measuring relatively high voltage values (9 + 12 V), but it becomes decisive when diagnosing elements that produce low-voltage signals, such as, for example, a lambda probe, where we are talking about measuring fractions of a volt.
4. Parallel monitoring of signal parameters, resistances and voltages in all control circuits is possible using a splitter. connected in series to the engine control unit connector. In this case, with the engine turned off or running, or while the vehicle is moving, the signal parameters at the terminals of the splitter are measured, from which a conclusion is drawn about possible defects.
5. For diagnostics of electronic systems, it is recommended to use the VAS5051B diagnostic complex or the VA-S5052A, VAS5054A or VAS5055 diagnostic testers. In addition, for this purpose, you can use a specialized automotive diagnostic computer, specially designed for complete diagnostics of most systems of modern cars (for example, ADC2000 from Launch HiTech). For this purpose, you can also use scanners and specialized diagnostic analyzers, for example, FDS 2000, Bosch FSA 560, or a regular personal computer with a special adapter, cable, and an installed OBD II browser program.
6. Some scanners, in addition to the usual diagnostic operations, allow you to print out the electrical circuit diagrams stored in the control unit memory when connected to a personal computer (if any are included), program the anti-theft system, monitor signals in the car circuits in real time.