Do not start the engine if you are not sure of the cleanliness and reliability of the fastening of the wire lugs on the battery terminals.
Do not use the charger to start the car.
Before disconnecting the wires from the battery (or connect them) don't forget to turn off the ignition (key in OFF position).
Be sure to disconnect the negative cable from the battery before servicing engine management components.
Before starting welding, be sure to disconnect the wires from the battery, also do not forget to disconnect the electrical connector of the control unit (ECU).
Do not allow the ECU to warm up to more than 80°C.
Keep all electrical connections clean and secure.
Before disconnecting any of the components of the engine management system, be sure to turn off the ignition (OFF).
Be sure to depressurize the system before removing components in the supply path of the power system. Remember that the system is under pressure all the time (even with the engine off).
When cleaning the engine, do not allow water to come into contact with the components of the engine management system.
When handling all components of the engine management system, especially the lambda probe, be careful.
Do not attempt to disassemble electronic components. If they fail, replace them with blocks.
Do not apply battery voltage directly to the fuel injectors.
Use of diagnostic equipment
Universal meter of parameters of electrical circuits (multimeter)
When testing voltage or resistance circuits, use only a digital multimeter with an impedance of at least 10 MΩ.
All measurements should be made with component electrical connectors connected unless otherwise noted in the test instructions. In this case, the measuring probe of the device is inserted into the connector from its reverse side. If the probes are not thin enough, they can be improved by attaching to their end a piece of wire thin enough not to damage the appropriate connector. Take care of reliable electrical and mechanical contact of the wire with the probe.
If the sealing cap or protective cover was removed from the connector to perform the test, be sure to reinstall it afterwards.
Probe lamp
Use probe lamps only where instructed to do so. To avoid damage to electronic components, use only probe lamps with a power of 3.6 W or less.
Use an accurate ammeter to check the lamp power (like a digital multimeter) - when the meter is turned on in series with the lamp and at a supply voltage of 12 V, the reading should not exceed 0.3 A (300 mA).
If a suitable probe lamp is not at hand, make one from an LED.
Note. When using an LED probe lamp as a signaling element, remember that the latter, by definition, passes current in only one direction. The test probe of the lamp must be connected to the positive side of the component being probed.
Preliminary checks
Note. Before you start looking for the causes of a failure in the engine control system itself, perform the checks listed below.
1. Check for fuel in the gas tank.
2. Check up a condition and reliability of contacts of all electric sockets and plugs of grounding of components of a control system of the engine.
3. Check the condition of the battery. Make the necessary corrections.
4. Check the condition of the air cleaner element. Replace if necessary.
5. Check fuel pressure.
6. Check the mechanical condition of the engine and the correctness of its settings.
7. Check up a condition and reliability of fastening of all vacuum hoses.
8. Check that there are no air leaks/vacuum losses through the intake manifold, throttle body, and air path plenum chamber.
9. Check the correct functioning of the controlled crankcase ventilation system (PCV).
10. Check the coolant level and make sure the engine is warmed up to normal operating temperature.