9.1.13. Contactless system of ignition

Features of the device
On the VAZ-2115 cars two types of systems of ignition can be applied: contactless (only on carburetor engines) and the system of ignition entering a complex of an electronic control system of the engine (system of injection of fuel). In the present chapter the contactless system of ignition is given, and another is described in the separate repair manual on a control system of the engine with the distributed fuel injection.

Fig. 9.39. Scheme of connections of a plait of wires of contactless system of ignition: 1 – spark plugs; 2 – ignition sensor distributor; 3 – ignition coil; 4 – switchboard; 5 – control unit of the electromagnetic valve of the carburetor; 6 – electromagnetic valve of the carburetor; 7 – trailer switch of the carburetor; 8 – ignition switch; 9 – assembly block; 10 – speed sensor; 11 – engine cooling system fan electric motor; 12 – sensor of turning on of the electric motor of the fan; And — blocks for connection with a forward plait of wires; B — the scheme of conditional numbering of plugs in blocks of the sensor distributor of ignition and the sensor of speed; In — to power supplies; — to a combination of devices (a signal for a tachometer); Е — to a combination of devices (a signal for a speedometer)

Fig. 7.1. Scheme of electric equipment of the VAZ-2115-20 cars (left half): 1 – block headlights; 2 – fog lights; 3 – air temperature sensor; 4 – engine cooling system fan electric motor; 5 – the blocks connected to a plait of wires of system of ignition; 6 – switch of a podkapotny lamp; 7 – a block for connection to a sound signal of single-wire type; 8 – sound signal; 9 – the sensor of level of the washing liquid; 10 – sensors of wear of blocks of forward brakes; 11 – oil level sensor; 12 – generator; 13 – podkapotny lamp; 14 – sensor of the index of temperature of cooling liquid; 15 – starter; 16 – rechargeable battery; 17 – relay of inclusion of fog lights; 18 – sensor of level of cooling liquid; 19 – sensor of level of brake fluid; 20 – backing light switch; 21 – motor-reducer of screenwash; 22 – sensor of a control lamp of pressure of oil; 23 – a block for connection to the electric motor of a washer of back glass; 24 – windshield washer electric motor; 25 – combination of devices; 26 – assembly block. Conditional numbering of plugs in blocks: And — blocks of block headlights; In — an electrogasoline pump block; With — blocks of the assembly block, the switch of ignition, a motor-reducer of screenwash; D — a plafond of illumination of salon

In fig. 9.39 the scheme of connections of a plait of wires of contactless system of ignition is shown. It is connected to blocks And (5 in fig. 7.1) a forward plait of wires.
In a plait of wires of contactless system of ignition there are also wires of a control system of the electromagnetic valve 6 of the carburetor, and also a wire for connection of the sensor 10 speeds and the sensor 12 of turning on of the electric motor of the fan.
The contactless system of ignition consists of the sensor distributor 2 ignitions, the switchboard 4, the coil 3 ignitions, candles of 1 ignition, the switch 8 of ignition and wires of high voltage. The power-supply circuit of primary winding of the coil of ignition is interrupted by the electronic switchboard. The operating impulses on the switchboard move from the contactless sensor located in the sensor distributor 2 ignitions.
The ignition sensor distributor — type 40.3706 or 40.3706-01, four-spark, unscreened, with vacuum and centrifugal regulators of an advancing of ignition, with the built-in microelectronic sensor of the operating impulses.
The switchboard — type 3620.3734, either 76.3734, or RT1903, or PZE4022. It will transform the operating sensor impulses to current impulses in primary winding of the coil of ignition.
The ignition coil — with the opened magnetic conductor, oil-filled, pressurized, the following types: 27.3705; 27.3705–01; 027.3705; ATE 1721; 8352.12. Or type 3122.3705 with the closed magnetic conductor, dry.
Spark plugs — the A17DVRM or A17DVRM1 type with pomekhopodavitelny resistors or similar foreign production.
The ignition switch — type 2110-3704005 or KZ-881 with the anti-theft locking device, with blocking against repeated inclusion of a starter without preliminary switching off of ignition and with nest illumination.

       PREVENTION
The contactless system of ignition is a system of ignition of high energy with broad use of electronics. Therefore not to be traumatized and to put electronic knots out of action, it is necessary to follow the following rules.
On the working engine not to concern elements of system of ignition (the switchboard, the coil, the sensor distributor of ignition and high-voltage wires).
Not to make launch of the engine by means of a spark gap and not to check operability of system of ignition "for a spark" between tips of wires of spark plugs and "weight".
Not to lay a wire of low voltage of system of ignition in one plait with wires of high voltage.
To watch reliability of connection with "mass" of the switchboard via fastening screws. It influences its trouble-free operation.
At the included ignition not to disconnect a wire from plugs of the rechargeable battery and not to disconnect the plug socket as at the same time on separate elements of its scheme there can be an increased tension from the switchboard and it will be damaged.
Check of the switch of ignition is described at the beginning of the 7th section in the head "Wires and safety locks".

Installation of the moment of ignition
The size of a corner of an advancing of ignition is specified in the appendix 3.

Fig. 2.58. The extreme sizes when grinding facets of valves: I \inlet valve; II \final valve

For check on the car of the moment of ignition there is a scale 1 (see fig. 2.58) in the hatch of a case of coupling and a tag 2 on a flywheel. One division of a scale corresponds 1 ° turn of a bent shaft. At combination of a tag on a flywheel with average (long) division of a scale pistons of the first and fourth cylinders are in VMT.


Fig. 9.40. Tags for installation of the moment of ignition: 1 – an ignition advancing tag on 5 °; 2 – an ignition advancing tag on 0 °; 3 – VMT tag on a pulley of a bent shaft

At an engine running in at the stand to determine the moment of ignition it is allowed by means of tags on a pulley of a bent shaft and on a forward cover of the drive of the camshaft (fig. 9.40) if on the engine the pulley for the generator 37.3701 drive is established odnoruchyevy.
It is possible to check and determine the ignition moment by means of a stroboscope, working in the following order:
– connect a clip "plus" a stroboscope to the plus plug of the rechargeable battery, a clip of "weight" — to the minus plug of the rechargeable battery, and attach a clip of the sensor of a stroboscope to a wire of high voltage of the 1st cylinder;
– start the engine and send the blinking stroboscope light stream to the coupling case hatch; if the moment of ignition is determined correctly, then when idling the engine the tag on a flywheel has to be in the situation corresponding to data of the appendix 3.
For adjustment of the moment of ignition stop the engine, weaken nuts of fastening of the sensor distributor of ignition and turn it on a necessary corner. For increase in a corner of an advancing of ignition the case of the sensor distributor should be turned clockwise, and for reduction — counterclockwise (if to take a detached view ignition sensor distributor covers). Tighten nuts of fastening and again check installation of the moment of ignition.

Fig. 9.9. Installation of the sensor distributor of ignition. The arrow showed an adjusting ledge on the case of auxiliary units

For convenience of adjustment of the moment of ignition on a flange of the sensor distributor of ignition there are divisions and the signs "+ "and" –", and on the case of auxiliary units — an adjusting ledge (see fig. 9.9). One division on a flange corresponds to eight degrees of turn of a bent shaft.
If there is a diagnostic stand with an oscilloscope, then with its help it is possible to check easily installation of the moment of ignition too, being guided by the maintenance instruction of the stand.

Check of devices of ignition at the stand
Ignition sensor distributor
Work check. Install the ignition sensor distributor on the control test bench for check of electric devices and connect it to the electric motor having the adjustable frequency of rotation.
Connect ignition sensor distributor conclusions to the ignition coil, with the switchboard and with the rechargeable battery of the stand it is similar to the scheme of system of ignition of the car. Connect four plugs of a cover to spark rated sportsmen which gap between electrodes is regulated.
Establish a gap of 5 mm between electrodes of rated sportsmen, turn on the electric motor of the stand and rotate the sensor distributor roller several minutes clockwise with a frequency of 2000 min.-1. Then increase a gap between electrodes to 10 mm and you watch whether there are no internal categories in the sensor distributor. They come to light on a sound or on easing and interruption of sparking on a rated sportsman of the test bench.
In operating time the sensor distributor of ignition should not make noise with any frequency of rotation of the roller.

Fig. 9.41. The scheme for removal of characteristics of the sensor distributor of ignition at the stand: 1 – switchboard; 2 – ignition sensor distributor; And — to the + plug" the stand; In — to the stand breaker plug

Removal of characteristics of an automatic advancing of ignition. Install the ignition sensor distributor on the stand, connect its conclusions to conclusions "3", "5" and "6" switchboards 1 (fig. 9.41) of the stand. "4" switchboards connect a conclusion to the stand plus plug, and a conclusion "1" – to the stand breaker plug. Establish a gap of 7 mm between rated sportsman electrodes.
Turn on the electric motor of the stand and rotate the ignition sensor distributor roller with a frequency of 500-600 min.-1. On the graduated disk of the stand note value in degrees at which one of four sparking is observed.

Fig. 9.42. Characteristic of the centrifugal regulator of the sensor distributor of ignition: And — an ignition advancing corner, a hail; n — the frequency of rotation of the roller of the sensor — the distributor of ignition, mines-1

Increasing in steps rotation frequency for 200–300 min.-1, determine the number of degrees of an advancing of ignition corresponding to the frequency of rotation of the roller of the sensor distributor of ignition by a disk. Compare the received characteristic of the centrifugal regulator of an advancing of ignition with the characteristic in fig. 9.42.
If the characteristic differs from provided on the drawing, then it can be normalized a podgibaniye of racks of springs of small weights of the centrifugal regulator. Up to 1250 min.-1 – turn in a rack of a thin spring, and over 1250 min.-1 – thick. For reduction of a corner increase a tension of springs, and for increase — reduce.
For removal of the characteristic of the vacuum regulator of an advancing of ignition connect the union of the vacuum regulator to the vacuum pump of the stand.
Turn on the electric motor of the stand and rotate the ignition sensor distributor roller with a frequency of 1000 min.-1. On the graduated disk note value in degrees at which there is one of four sparking.

Fig. 9.43. Characteristic of the vacuum regulator of the sensor distributor of ignition: And — an ignition advancing corner, a hail; Р — depression, a gp (mm of mercury.)

Smoothly increasing depression, through each 26,7 gpa (20 mm of mercury.) note number of degrees of an advancing of ignition of rather initial value. Compare the received characteristic to the characteristic in fig. 9.43.
Pay attention to the clearness of a reset after removal of vacuum of a plate on which the contactless sensor is fixed.
Check of the contactless sensor. From an exit of the sensor stress is removed if in its gap there is a steel screen. If there is no screen in a gap, then tension at the exit of the sensor is close to zero.

Fig. 9.44. The scheme for check of the contactless sensor on the removed ignition sensor distributor: 1 – ignition sensor distributor; 2 – resistor 2 kOhm; 3 – the voltmeter with a scale limit not less than 15 V and with an internal resistance not less than 100 kOhm; 4 – view of the plug socket of the sensor distributor of ignition

On the ignition sensor distributor removed from the engine the sensor can be checked according to the scheme provided on fig. 9.44 at the supply voltage of 8-14 Century.
Slowly rotating the ignition sensor distributor roller, measure by the voltmeter tension at the sensor exit. It has to change sharply from minimum (no more than 0,4 In) to maximum which has to be no more than 3 V less than supply voltage.

Fig. 9.45. The scheme for check of the contactless sensor on the car: 1 – ignition sensor distributor; 2 – the transitional socket with the voltmeter having a scale limit not less than 15 V and internal resistance not less than 100 kOhm; 3 – view of the plug socket of the sensor distributor of ignition

On the car the sensor can be checked according to the scheme provided on fig. 9.45. Between the plug socket of the sensor distributor of ignition and the socket of a plait of wires the socket 2 with the voltmeter is connected transitional. Include ignition and, slowly turning a special key a bent shaft, the voltmeter check tension at the sensor exit. It has to be within stated limits.
Ignition coil
Check resistance of windings and resistance of isolation.
At oil-filled coils resistance of primary winding at 25 °C has to make (0,45±0,05) Ohms, and a secondary winding (5±0,5) kOhm. The dry coil with the closed magnetic conductor has to have resistance of windings respectively (0,388±0,039) Ohms and (4,23±0,42) kOhm.
Isolation resistance on weight has to be not less than 50 megohms.
Switchboard

Fig. 9.46. The scheme for check of the switchboard: 1 – rated sportsman; 2 – ignition coil; 3 – switchboard; 4 – resistor of 0,01 Ohms of ±1%, not less than 20 W; And — to the generator of rectangular impulses; In — to an oscillograph

The switchboard is checked by means of an oscillograph and the generator of rectangular impulses according to the scheme provided on fig. 9.46. Output resistance of the generator has to be 100–500 Ohms. An oscillograph it is desirable to apply two-channel. the 1st channel — for generator impulses, and the 2nd for switchboard impulses.

Fig. 9.47. A form of impulses on the oscillograph screen: I \switchboard impulses; II \generator impulses; And — time of accumulation of current; In — the maximum size of current

On the 3 and 6 plugs of the switchboard the rectangular impulses imitating sensor impulses move. Frequency of impulses from 3,33 to 233 Hz, and porosity (the period relation to T/TI impulse duration) is equal to 3. The maximum tension of Umax – 10 V, and the minimum Umin no more than 0,4 In (fig. 9.47, II). At the serviceable switchboard the form of impulses of current has to correspond to the oscillogram of I.
For switchboards 3620.3734 and 76.3734 at supply voltage (13,5±0,5) B size of current (V) have to be 7,5-8,5 A. Time of accumulation of current (A) is not normalized.
For the RT1903 switchboard at supply voltage (13,5±0,2) B and the frequency of impulses of 25 Hz current makes 7-8 A, and time of accumulation of current of 5,5-11,5 ms.
For the PZE4022 switchboard at supply voltage (14±0,3) B and the frequency of 25 Hz the size of current makes 7,3-7,7 A, and time of accumulation of current is not normalized.
If the form of impulses of the switchboard is distorted, then there can be interruptions in sparking or it can happen to delay. The engine will overheat and not to develop rated power.
Spark plugs
Or polluted before test clear spark plugs with a deposit on special installation by a stream of sand and blow compressed air. If a deposit of light brown color, then it can be not deleted as it appears on the serviceable engine and does not break work of system of ignition.
After cleaning examine candles and adjust a gap between electrodes. If on the insulator of a candle there are chips, cracks or welding of a side electrode is damaged, then replace a candle.
Check a gap (0,7–0,8 mm) between electrodes of a candle the round wire probe. It is impossible to check a gap the flat probe as at the same time dredging on a side electrode which is formed during the work of a candle is not considered. Regulate a gap a podgibaniye only of a side electrode of a candle.
Test for tightness. Screw a candle in the corresponding nest at the stand and tighten a dynamometer key the moment 31,4–39,2 N · m (3,2–4 kgfs · м). Create pressure of 2 MPas (20 kgfs/cm2) in the camera of the stand.
Drop from a butterdish on a candle several drops of oil or kerosene; if tightness is broken, then there will be vials of air, usually between the insulator and the metal case of a candle.
Electric test. Screw a candle in a nest at the stand and tighten the moment stated above. Adjust a gap between rated sportsman electrodes on 12 mm that corresponds to voltage of 18 kV, and then the pump create pressure of 0,6 MPas (6 kgfs/cm2).
Establish a tip of a wire of high voltage on a candle and give on it impulses of high voltage.
If in an eyepiece of the stand the full-fledged spark is observed, then the candle is considered excellent.
If sparking happens between rated sportsman electrodes, then it is necessary to lower pressure in the device and to check with what pressure there occurs sparking between candle electrodes. If it begins with a pressure below 0,3 MPas (3 kgfs/cm2), then a candle — defective.
Several sparking on a rated sportsman is allowed; if sparking is absent on a candle and on a rated sportsman, then it must be assumed that on the insulator of a candle there are cracks and that the category happens inside, between the weight and electrodes. Such candle is discarded.
Check of elements for suppression of a radio noise
For suppression of a radio noise treat elements:
– the resistor in an ignition sensor distributor rotor. Size of resistance of the resistor of 1 kOhm;
– wires of high voltage with the distributed resistance (2550±270) Ohms/m;
– resistors of 4-10 kOhm in spark plugs;
– the condenser, with a capacity of 2,2 мкФ, located in the generator.
Serviceability of wires and resistors is checked by an ohmmeter. Check of the condenser is described in the subsection "Generator".

Repair of the sensor distributor of ignition
Removal
Slow down the car the parking brake and disconnect a wire from the minus plug of the rechargeable battery.

Fig. 2.58. The extreme sizes when grinding facets of valves: I \inlet valve; II \final valve

Take out a cap from the viewing hatch of a case of coupling. Rotating a bent shaft for a bolt of fastening of a pulley, turn it before combination of a tag on a flywheel with average division of a scale (see fig. 2.58).
Disconnect from the sensor distributor of ignition of a wire and a vacuum hose. Turn off fastening nuts, remove an arm of fastening of high-voltage wires and the sensor distributor of ignition.
Installation
The roller of the sensor distributor of ignition connects to a camshaft shaft only in one situation. Therefore before installation turn the ignition sensor distributor roller in such situation that cams of the coupling of the roller were against camshaft grooves.

Fig. 9.9. Installation of the sensor distributor of ignition. The arrow showed an adjusting ledge on the case of auxiliary units

Oil engine and put on a sealing ring an ignition sensor distributor flange. Install the ignition sensor distributor on the case of auxiliary units in such situation that average division on a flange of the sensor distributor of ignition was against an adjusting ledge on the case of auxiliary units (see fig. 9.9). Establish an arm of fastening of wires of high voltage. Fix an arm and the sensor distributor of ignition by nuts.
Attach to the sensor distributor of ignition of a wire and a vacuum hose.
Check and adjust the ignition moment.
Dismantling
You make dismantling for replacement of any details in the following order:


Fig. 9.48. Ignition sensor distributor details: 1 – coupling; 2 – case; 3 – vacuum regulator; 4 – centrifugal regulator; 5 – contactless sensor; 6 – a basic plate of the sensor with the bearing; 7 – holder of the forward bearing of the roller; 8 – cover; 9 – rotor; 10 – filter; 11 – the holder of the forward bearing of the roller assembled with a basic plate of the sensor; 12 – washer of fastening of wires; 13 – the conducted plate of the centrifugal regulator with the screen; 14 – the roller with the leading plate of the centrifugal regulator; 15 – small weights; 16 – epiploon

– uncover 8 (fig. 9.48), a rotor 9 and the filter 10;
– disconnect draft of the vacuum regulator 3 from a basic plate of the 6th sensor, unscrew screws of fastening and remove the vacuum regulator;
– unscrew screws of fastening and remove a basic plate 6 assembled with the sensor 5 and the holder 7;
– remove a spring from the coupling 1, remove a pin and remove the coupling and adjusting washers from the roller;
– take out from the case 2 the roller with the centrifugal regulator 4 and washers.
Assembly is made as it should be, the return to dismantling. At assembly it is necessary to provide with selection of adjusting washers an axial free wheeling of the roller no more than 0,35 mm.