Warning 1: when working with ignition elements, extreme precautions must be taken, since this system generates extremely high voltage, which can be present not only at the contacts of the coils and spark plugs, but also at the contacts of other elements and devices included in the system circuit.
Warning 2: The following procedures require turning the engine crankshaft. Keep connecting wires, loose clothing, long hair, etc. away. on moving engine elements (drive belt, cooling fan, etc.).
1. Before drawing a conclusion about a malfunction of the ignition system in a car whose engine does not start, it is necessary to perform a number of initial checks.
- A) Make sure the battery terminals are securely tightened and free of deposits.
- b) Check battery performance (see subsection 3). Replace the battery if necessary.
- With) Inspect the wires and connectors at the connections between the coils and the ignition system control unit.
- d) Inspect the appropriate fuses located in the distribution block, which is located in the engine compartment (see chapter 12). If it turns out that the fuse has blown, replace it after eliminating the cause of the burnout.
2. If the crankshaft rotates and the engine does not start, or if obvious misfires are noted, make sure that sufficient secondary ignition voltage is supplied to the spark plugs to produce a spark.
3. Disconnect the fuel system by removing the fuel pump relay located in the engine compartment junction block (see chapter 12).
4. Disconnect the coil (see subsection 7) from one of the spark plugs and connect a special system tester to the connector of the protective boot (which can be purchased at most automotive stores). Connect the tester through its clamp to a bolt or metal bracket of the engine (see illustration). Rotate the crankshaft and look at the tip of the tester. A bright blue spark should form at the tip. The presence of a weak or uneven spark means the same thing as its absence.
6.4 To check using a tester, you must disconnect the coil and connect the device to the connector in the spark plug case, and also connect the tester to the grounding point. Turn the crankshaft, if sufficient voltage is generated in the circuit, a spark will jump between the spark plug electrodes and the tester body (the presence of a weak or uneven spark means the same thing as its absence)
5. The presence of a spark indicates that sufficient voltage is supplied to the spark plugs to ignite the mixture. Repeat the described procedure on the remaining cylinders to ensure that the coil is working properly (ek) and control systems, as well as the suitability of spark plug boots. If the ignition system is working properly, then the cause of the problem may be mechanical in nature or a consequence of a malfunction of the fuel system elements. It should be noted that spark plugs may not produce a spark due to contamination. Remove and inspect them as described in Chapter 1, or make a replacement.
6. If there is no spark on any of the cylinders, inspect the PCM I fuse located in the engine compartment distribution block.
7. If there is no spark present on one or more cylinders, disconnect the ignition coil connector and check the voltage supply from the battery to the contact terminal «A» when the ignition key is in the ON position. If necessary, repair the circuit that is not receiving power.
8. If the engine does not start due to lack of spark or misfire, check the functionality of the ignition system according to the engine type as follows.
Warning: The following procedure requires turning the engine crankshaft. When turning on the starter, keep loose items of clothing, long hair, etc. away. drive belt and cooling fan as this could result in serious injury.
9. Make sure that voltage from the battery is supplied to the coils through the ignition switch. Connect the electrode of the twelve-volt test lamp to the negative terminal of the battery. Disconnect the connector of one of the ignition coils and check that there is voltage at the pink terminal of the connector. Power is supplied when the ignition key is in the ON position. If no power is noted, examine the circuit between the engine compartment junction block and the coil connector. Also inspect the fuses. Make sure there is continuity in the ground loop that is connected to the black pin of the coil connector. If it is determined that voltage is applied to the coil, but it does not generate a spark, then the cause of the malfunction should be sought directly in the coil, crankshaft position sensor, PCM control unit, or in the wiring.
10. Make sure that an excitation signal is supplied to the coil from the PCM. Connect one electrode of the test lamp to the positive terminal of the battery, and connect the other electrode to the control circuit terminal (this pin is central in the connector). Turn the crankshaft. If the control circuit is operational, then rotation of the crankshaft should be accompanied by flashes of the lamp. If necessary, perform the described check on each coil. If it is determined that the coil is receiving an excitation signal, and the power and ground circuits are intact, but no spark is produced, replace the coil. If the coil does not receive an excitation signal, check the operation of the crankshaft position sensor (see chapter 6). If it is determined that the sensor is in good condition, examine the sections of the circuits connecting the coil to the PCM. If the circuits are confirmed to be in good condition, contact a dealer to have the PCM diagnosed.