10.3.5. Microprocessor system of ignition

The microprocessor system of ignition is intended for ignition of working mix in engine cylinders with installation of an optimum angle of an advancing of ignition for this power setting. This system operates operation of the electromagnetic valve of the economizer of compulsory idling (ECI).
By means of microprocessor system of ignition more economic operation of the engine is reached; at increase in its power indicators operation of the engine with a detonation is excluded and norms on toxicity of exhaust gases are carried out. This system is more durable and it is more reliable in comparison with classical system of ignition.
In it there are no details which are exposed to wear (except electrodes of spark plugs).

Fig. 9.81. Numbering of conclusions of sockets (view from the party of wires): XI \socket of the control unit of system of ignition; X2 — the socket of sensors of temperature and a detonation; HZ — the socket of sensors of provision of a bent shaft and absolute pressure





Fig. 9.80. Electric circuit of system of ignition: B63 — the sensor of absolute pressure; B70 — the sensor of temperature of cooling liquid of a control system of the engine; B74 — the synchronization sensor; B92 — the detonation sensor; D5 — the system control unit tightening; F1, F2, F3, F4 — spark plugs; T1, T4 — ignition coils; Y3 — the EPHH electromagnetic valve; X2 — a connector with бортсетью the car; X51 — diagnostics block; I \numbers of conclusions
Symbols of flowers of wires: B — white; — blue; — yellow; 3 — green; To — red; Кч — brown; About — orange; Р — pink; With — gray; H — black, F — violet; BS — white-gray; BCh — white-black; ZhS — yellow-gray; ZB — green-white; KS — red-gray; SG — gray-blue; SK — gray-red; RZ — pink-green. A part of wires can have digital marking




The microprocessor system of ignition consists of the control unit, two coils of ignition, spark plugs, sensors, the EPHH electromagnetic valve and a control lamp of diagnostics. Structure of system and the scheme of connections it is shown on rice. 9.80, and in fig. 9.81 numbering of conclusions of sockets is given.
Control unit of microprocessor system of ignition
The microprocessor electronic control unit of MIKAS 5.4.209.3763.004 * is intended for:
- formations of impulses of electric current for operation of coils of ignition with an optimum angle of an advancing of ignition;

* The MIKAS 7.1.243.376-3-01 control unit can be installed on parts of cars.

- formations of impulses of electric current for operation of the EPHH electromagnetic valve;
- ensuring work of all system in standby mode (in case of failure of separate elements of system);
- diagnostics of malfunctions of system.
The basic element of the block — the microprocessor — makes all calculations and development of all necessary data ensuring functioning of system of ignition and EPHH. The block works in a set with the following sensors and knots:
- sensor of provision of a bent shaft and turns (synchronization sensor);
- the sensor of absolute pressure of air in an inlet pipe of the engine;
- engine temperature sensor;
- detonation sensor;
- ignition coils;
- EPHH electromagnetic valve;
- control lamp of diagnostics.
Microprocessor system of ignition and EPHH work as follows.

Fig. 3.1. Governing bodies




At inclusion of ignition on the dashboard the signaling device (1 or 33 lights up (see fig. 3.1). At this time the microprocessor works in the self-diagnostics mode. After the termination of this mode the control lamp dies away if malfunctions are not found, or burns if malfunction is found. If the signaling device went out, the system is serviceable and ready to work. When scrolling the engine a starter on signals of the sensor of provision of a bent shaft the control unit gives impulses of electric current in ignition coils for ensuring work of candles according to an operating procedure of cylinders of the engine 1-3-4-2. High voltage from each coil of ignition at the same time moves to two candles:
- to a candle in the cylinder where there is a step of compression of working mix (for example, the 1st cylinder) and which electric discharge ignites it;
- at the same time there is an electric discharge in the second candle in the fourth cylinder where there is a step of an exit of the fulfilled gases; this category does not influence operation of the engine.
For definition of an optimum angle of an advancing of ignition the block uses data from all sensors and the data put in his memory. For each concrete power setting the control unit issues the data on an ignition advancing corner. The block continuously corrects the output data on the changing data of sensors. The block also operates work of the EPHH system blocking supply of fuel during the operation of the car in the mode of the movement by "setup" with not switched-off engine. At such mode there is no need for supply of fuel in the engine, economy of fuel thereby is provided and emission of toxic substances in the atmosphere decreases. In case of failure of separate sensors or their chains (except the sensor of provision of a bent shaft) the block switches over works to standby mode, using the data put in his memory. At the same time on the dashboard the control lamp lights up; it will constantly burn before malfunction elimination.
Operation of the block in standby mode allows operation of the car before carrying out the qualified repair work.
During the operation of the engine in standby mode of operation of the block acceleration performance, toxicity worsens and fuel consumption can increase.
The control unit is fixed to a front guard arm by special bolts with the curtailed heads (for an exception of unauthorized renting of the block from the car).
Dismantle and installation of the block can be made in two ways.
Way 1:
- to drill a drill with a diameter of 5,2 — 5,5 mm special bolts and to remove the block;
- to cut in welded nuts on an arm M6 carving, to install the block into place and to fix it by M6 screws.
Way 2:
- to drill a drill with a diameter of 6,4 — 6,6 mm special bolts and to remove the block;
- to install the block into place and to fix it by standard screws and nuts of M6.
Malfunctions of system of ignition and EPHH
In the control unit there is a self-diagnostics mode by which it is possible to define malfunctions in system.
If the control unit in the mode of self-diagnostics cannot define malfunction, then it is necessary to use the special DST-2 device with the corresponding cartridge (the cartridge with the program). At the same time it is necessary to be guided by the instruction attached to the device.
The control unit in the mode of self-diagnostics gives light codes on a control lamp. The digital code is assigned for each malfunction. The digital code is determined by number of inclusions of a control lamp. At first consider number of inclusions of a lamp for determination of the first figure of a code (for example, figure 1 — one short inclusion of 0,5 c, figure 2 — two short inclusions, then there is a pause of 1,5 pages. After it consider number of inclusions for determination of the second figure of a code, then the third then there is a pause in 4 with, defining the end of a code). If the code three-digit, the first figure is highlighted lasting 1 page.
For transfer of the control unit to the self-diagnostics mode:
- to switch-off the rechargeable battery on 10 — 15 with and again to connect;

Fig. 9.82. Diagnostic socket: 1 — the diagnostic socket; 2 — an additional wire




- to start the engine and to allow it to work 30 — 60 with idling — a separate wire to connect conclusions of the diagnostic socket according to fig. 9.82. The socket is installed in motor office on a front guard on the left side.
After transfer of the control unit to the self-diagnostics mode the control lamp has to highlight a code 12 three times that testifies to the beginning of work of the mode of self-diagnostics. The following codes will display the available malfunction or several malfunctions. Each code repeats three times.
After indication of all codes of the available malfunctions the code 12 is highlighted three times and indication of codes repeats.
If the control unit cannot define malfunction or there are no malfunctions, the code 12 is highlighted. Diagnostic codes of malfunctions of microprocessor system of ignition and EPHH are given in tab. 9.8.

Table 9.8. Diagnostic codes of malfunctions of microprocessor system of ignition and EPHH
Diagnostic codes of malfunctions of microprocessor system of ignition and EPHH
code No.
Malfunction
12
The mode of self-diagnostics is included
15
Short circuit in a chain of the sensor of absolute pressure of air
16
Break of a chain of the sensor of absolute pressure of air
21
Short circuit in an engine temperature sensor chain
22
Break in an engine temperature sensor chain
25
Low level of tension in car bortset
51, 52
61-65
Malfunction of the control unit
53
Malfunction of the sensor of provision of a bent shaft or high level of hindrances in car bortset
181
Short circuit in a chain of a control lamp of diagnostics (is defined only by the DST2 device)
182
Break in a chain of a control lamp of diagnostics (is defined only by the DST2 device)
197
Short circuit in an EPHH valve chain
198
Break of a chain of the EPHH valve


Sensor of provision of a bent shaft of the engine (synchronization)
The inductive sensor defines the angular provision of a bent shaft of the engine, synchronization of operation of the control unit with working process of the engine and frequency of its rotation.

Fig. 9.83. Sensor of provision of a bent shaft: 1 — windings; 2 — the case; 3 — a magnet; 4 — a sealant; 5 — the drive; 6 — a fastening arm; 7 — a magnetic conductor; 8 — a synchronization disk




The sensor is installed in a forward part of the engine on the right side. The device of the sensor is shown in fig. 9.83.
The sensor is an inductive coil 1 with a magnet 3 and the core 7. The sensor works together with the gear disk of synchronization 8 established on a pulley of a bent shaft. Passing by an end face of the core 7 of the sensor of teeths of a disk of synchronization 8, causes change of a magnetic flux in the sensor. Change of a magnetic flux causes emergence of alternating electric current in the sensor coil. The arising alternating voltage is transferred to the control unit which processes them with other signals of sensors and forms parameters of electric impulses for operation of coils of ignition.
At failure of the sensor of provision of a bent shaft or its chains work of system of ignition and according to the engine stops.
Serviceability of the sensor can be checked an ohmmeter. Resistance of the coil of the sensor has to be in limits of 850 — 900 Ohms; a gap between the core of the sensor and teeths of a disk synchronization — within (1±0,5) mm.
Better check of serviceability of the sensor needs to be made the DST-2 device when scrolling the engine a starter.
To replace the faulty sensor.
Detonation sensor
The sensor defines a detonation during the operation of the engine. A detonation — unauthorized spontaneous ignition of working mix in engine cylinders. During the operation of the engine in such mode there are strong vibration and thermal loads of engine details.
Operation of the engine with a detonation can lead to destruction of details of the engine (for example, the piston, laying of a head of the block, etc.).
The sensor of a detonation is installed on the right side of the block of cylinders in a zone of the quarter cylinder.

Fig. 9.84. Detonation sensor: 1 — the plug; 2 — the insulator; 3 — the case; 4 — a nut; 5 — an elastic washer; 6 — an inertial washer; 7 — a piezoelement; 8 — a contact plate




The device of the piezoelectric sensor of a detonation is shown in fig. 9.84.
Main elements of the sensor: quartz piezoelement 7 and inertial weight 6 (washer). During the operation of the engine there is a vibration of its details. The inertial mass of the 6th sensor influences a piezoelement 7; in it there are electric signals of a certain size and a form. Emergence of a detonation in operation of the engine sharply increases vibration that increases amplitude of tension of electric signals of the sensor. Electric signals of the sensor are transmitted to the control unit. On detonation sensor signals the control unit corrects an ignition advancing corner before the termination of a detonation. At failure of the sensor or its electric chains the control unit signals the driver inclusion of a control lamp.
Serviceability of the sensor can be checked only during the operation of the engine the DST-2 device.
The faulty sensor should be replaced.
Temperature sensor
The sensor of temperature of cooling liquid is the semiconductor element changing the conductivity depending on surrounding temperature.
The sensor is installed in a branch pipe of the thermostat and intended for determination of temperature of cooling liquid of the engine. The sensor is included in the electronic scheme of the control unit which in power failure size in a sensor chain (depending on temperature) corrects an ignition advancing corner.
At emergence of malfunction in the sensor or in sensor chains the control unit signals the driver inclusion of a control lamp.
Serviceability of the sensor needs to be checked the DST-2 device; at its absence — in power failure size in a sensor chain at various temperatures.

Fig. 9.85. Electric circuit of check of the sensor of temperature: 1 — resistance variable 10 kOhm; 2 — the rechargeable battery; 3 — the voltmeter, 4 — the milliamperemeter; 5 — the sensor




For check it is necessary to collect the scheme (see fig. 9.85). With a resistance of 1 on the milliamperemeter 4 to establish current in a chain 1 — 1,5 мА. At +25 °C the voltmeter 4 has to show tension of 2,957 — 3,022 Century.
Changing the surrounding temperature of the sensor, to carry out power failure measurements by the voltmeter 3. It has to keep within the limits provided below:
+40 °C — 2,287 — 2,392 IN
+90 °C — 3,642 — 3,737 IN
The faulty sensor needs to be replaced.
Sensor of absolute pressure
The sensor of absolute pressure measures pressure (discharge) of air in an inlet pipe of the engine. The sensor is installed on a front guard under a cowl and connected by a hose to an inlet pipe of the engine. The sensor is a film (membrane) on which the resistive layer changing the resistance depending on the bend of a membrane depending on discharge in an inlet pipe is applied. As a part of the sensor there is an electronic amplifier processing the data obtained from a resistive layer of a film and transferring them to the ignition control unit. Serviceability of the sensor is checked by the DST-2 device as a part of the car.
Ignition coil
Coils of ignition are intended for production of electric current of high voltage for ignition of working mix in engine cylinders.

Fig. 9.86. Ignition coil: 1 — a magnetic conductor; 2 — the case; 3 — the coil; 4 — a winding secondary; 5 — a winding primary; 6 — a high-voltage conclusion; 7 — a compound; 8 — a fastening bracket




Ignition coils (2 pieces) are installed from above the engine. The device of the coil of ignition is shown in fig. 9.86. The coil of ignition are a transformer. On a magnetic conductor 1 primary winding 5 is reeled up, and from above it sections reeled up a secondary winding 3. Windings are put into the plastic case 2. The space between windings is filled with a compound 7. On the case there are conclusions of low and high voltage 6. Electric impulses of low voltage come to the ignition coil from the control unit. In the ignition coil they are transformed to electric impulses of high voltage which on wires is transferred to candles. Electric discharge happens at the same time in two candles of the first and fourth cylinders or the second and third cylinders.
For example, one electric discharge happens in a candle of the first cylinder when there the compression step comes to an end; the second category happens in a candle of the fourth cylinder when there is an exhaust step. Electric discharge in a candle of the fourth cylinder at an exhaust step does not influence operation of the engine.
At further turn of a bent shaft electric discharge will happen in a candle of the fourth cylinder, at the end of a compression step, and in the first cylinder — electric discharge in a candle will happen at an exhaust step.
For check of operability of coils disconnect both high-voltage wires from tips of candles of one coil of ignition. Arrange tips of wires at distance of 5 mm from each other. When scrolling the engine a starter in an interval between tips has to periodically (in a step of operation of cylinders of the engine) to occur electric discharge. The same method checks the second coil of ignition.
Resistance of windings of the coil of ignition at a temperature of +25 °C has to be in limits:
- primary 0,4 — 0,5 Ohms;
- secondary 5 — 7 kOhm.
To replace the faulty coil.
Spark plugs
It is recommended to apply the A14DVR spark plugs or import analogs to ZMZ-4061, ZMZ-4063 engines.
When checking candles of A14DVR it must be kept in mind that in the insulator of a candle the resistive filler for decrease in level of a radio noise is placed. Resistance size between the top conclusion and the central electrode of a candle has to be no more than 10 000 Ohms; a gap between candle electrodes — 0,7 — 0,85 mm.
Wires of high voltage
Wires are made of a wire of the PVVP or PVPPV brand. This wire has the plastic core with a ferrite filler. On the core the spiral by a wire with a high ohmic resistance is reeled up (2000+200 Ohms on 1 m of length). From above the spiral is covered with plastic isolation. The wire of PVVP or PVPPV reduces the level of the radio noise created by system of ignition.
During operation it is necessary to watch that on a surface of wires of high voltage oil as their surface will intensively become soiled that in turn will cause leakages of a high-tension current and breakdown of isolation did not get. At hit of oil on wires they should be wiped with the rag moistened in gasoline.
If necessary it is necessary to check serviceability of a current carrying vein of a wire an ohmmeter. Resistance of wires to the 1st and 2nd cylinders has to be no more than 1000 Ohms, and wires to 3 and 4 cylinders — no more than 900 Ohms.
Tips of spark plugs

Fig. 9.87. Tip of spark plugs: 1 — a nest contact; 2 — a core; 3 — a spring; 4 — pomekhopodavitelny resistance; 5 — a tip; 6 — the case; 7 — a lock spring



Wires of high voltage are connected to candles through special tips. The device of a tip is shown in fig. 9.87. Resistance of a serviceable tip has to be no more than 8000 Ohms.