General information
All components of the power supply system are characterized by a high degree of reliability. Most failures, as a rule, turn out to be associated with a violation of the quality of the electrical wiring contact connections. Breakdowns of explosive electrical wiring most often occur due to pollution, moisture or violation of the integrity of the insulation. Before finally establishing your opinion about the failure of any of the components of the system, carefully check the condition of the wiring of the corresponding circuit.
The compilers of this Guide do not recommend checking the condition of the explosive wiring in such a popular way as disconnecting the wires from the candles and approaching the terminal lug to the surface of the block - such a procedure is fraught not only with electrical injury, but also with failure of the control module or ignition coil. If the stability of the engine speed is disturbed, do not disconnect the BB wires from the spark plugs!
The following checks should be performed for obvious problems such as starter failure or misfiring. Some malfunctions are not so obvious and may not appear at all due to the automatic transition of the control system to the emergency mode of operation. Such failures usually make themselves felt only indirectly (to increase fuel consumption, violate the stability of idle speed, reduce the power developed by the engine, etc.), - seek advice from car service specialists.
Engine won't start
Failure to start the engine may be due to the failure of the immobilizer of the anti-theft system - turn off the alarm and the immobilization system (see chapter Manual).
1. If the engine does not crank when the starter is engaged, or cranks very slowly, check the starter and battery. Connect a voltmeter to the battery terminals and measure the voltage while cranking the crankshaft with the starter.
Do not operate the starter continuously for more than 10 seconds. If the voltmeter registers a reading of 9.5 V or less, check the condition of the battery, starter, and charging system components (see Charge and launch systems).
2. If the engine does not start despite the serviceability of turning it with a starter, check the condition of all explosives in the ignition system circuit.
3. Following the manufacturer's instructions, connect a stroboscope and turn the engine over with a starter - if the lamp on the stroboscope lights up, therefore, voltage is being properly supplied to the spark plugs. Check the condition of the spark plugs (see chapter Current service).If the lamp does not light up, check the condition of the BB wiring (see chapter Current service).
4. If sparking is not working properly, check the condition of the ignition coil/module by replacing it with a known good one, or by checking the resistance of the windings. If, after replacing the coil / module, the engine starts to start, do not rush to throw away the old coil - first the condition of its contact terminals and the reliability of connecting electrical wiring to them.
If the coil is in order, the cause of the failure may lie in the malfunction of the powerful buffer output stage included in the ECM, one of the information sensors of the engine management system, or any related unit. In such a situation, the corresponding diagnostic code is usually entered into the memory of the ECM processor - the fault codes are read using special diagnostic equipment (see chapter Engine electrical equipment).
Misfire
The cause of misfiring is most often a violation of the quality of the terminal connections of the electrical wiring of the coil / ignition module or any of the information sensors.
1. Switch off ignition and check up reliability of fixing of all contact sockets of system of ignition.
2. Check the condition of the electrical wiring, - evaluate the reliability of fixing the spark plug wires in the intermediate clamps, make sure that the wires do not touch the metal parts of the power unit. If the wire touches the metal and its insulation is damaged, then when the engine is running, the spark will not be applied to the candle, but to the ground. If there is evidence of even slight damage to the insulation of at least one wire, replace the entire set.
The most reliable way to check is to replace the spark plug wiring kit with a known good one.
Replace the wires one by one to avoid disturbing the ignition order. Be careful not to damage the insulation or connector.
If the BB wiring is good, misfiring could be caused by a failed coil/module or one of the spark plugs. Change spark plugs (see chapter Current service). Failure or contamination of the crankshaft position sensor can also lead to misfiring (see chapter Power and exhaust systems). If, during self-checks, it is not possible to identify the cause of the violation, the car should be driven to a service station to perform a complete diagnosis of the control system using special equipment (see OBD system - general information and Application of oscilloscope to observe working control system).
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