Contents: Contactless sensor ↓ Switch ↓ Ignition coil and high tension wires ↓ Ignition switch ↓ Testing of radio interference…↓
Caution: If the vehicle is equipped with a high-energy contactless transistor ignition system, do not disconnect the high-voltage wires or check the ignition circuits for sparks while the engine is running, as this may result in injury, as well as burnout of the high-voltage insulation and failure of the ignition system.
For the same reason, it is not allowed to start the engine using a spark gap between the high-voltage wire and the central terminal of the ignition distributor sensor. In addition, it is strictly forbidden to perform preventive work on the distributor sensor with the ignition on.
When servicing the vehicle, check the reliability of the connections of the high-voltage wires to the ignition distributor, coil and spark plugs.
Do not disconnect the wires from the battery terminals while the engine is running, as this may damage the switch.
Contactless sensor
Check the functionality of the contactless sensor located in the ignition distributor sensor using an indicator assembled according to the circuit shown in Fig. 240. The indicator uses resistors of the MLT type, 1 W; capacitors C1 of the KLS1 type and C2 of the K53-14 type. The HL1 indicator lamp is A12 car lamp, 3 watts. Instead of the KT816B transistor, you can use a KT814B transistor. The indicator wires are soldered in a three-terminal block W1 of the same type that is attached to the ignition switch sensor on the car.
To check the contactless sensor, connect the indicator to the ignition distributor sensor instead of the ignition system wiring harness and turn the engine crankshaft with a starter or a special key for the bolt on the crankshaft. If the HL1 lamp blinks when the crankshaft rotates, then the contactless sensor is working properly.
The serviceability of the contactless sensor can also be checked on the stand. The procedure for this check is described in the stand instructions. This method is more accurate, as it allows you to check the magnitude of the voltage pulses emitted by the sensor using a voltmeter.
Switch
The operability of the switch can also be checked using a lamp of the A12 type, 3 W. To check, disconnect the brown wire with red stripes from the ignition coil, coming from the terminal "I" of the switch, and connect the tip of the wire to the test lamp. Connect the other lead of the lamp to the terminal "+B" of the ignition coil and turn the engine with the starter. If the lamp blinks when the engine crankshaft rotates, then the switch sends current pulses to the ignition coil.
The article is copied from the website (VAZbook)
The described method allows only a rough estimate of the switch's performance - whether it produces current pulses or not. Pulse parameters (size and duration, shape) cannot be checked by this method. And they can seriously affect the engine operation, especially at high crankshaft speeds. 'Therefore, the following test of the switch on the stand using an oscilloscope and a rectangular pulse generator is more accurate.
Ignition coil and high tension wires
Check the functionality of these elements using a high-voltage arrester. The simplest arrester consists of two sharpened metal rods, the gap between which can be adjusted. Fasten the rods to a plate made of electrically insulating material (plastic or ceramic).
To check the ignition coil, disconnect the high-voltage central wire from the ignition distributor and connect it to the spark gap electrode. The second terminal of the spark gap is connected to the car body and the air gap between the spark gap electrodes is set to 7-10 mm. If, when the engine is rotated by the starter, uninterrupted sparking is observed between the spark gap electrodes, then the ignition coil and the high-voltage central wire are in good condition.
Connect the central wire to the ignition distributor and connect the spark plug wires to the spark gap one by one, and check the functionality of these wires in the same way. Possible causes of interruptions in spark formation may be cracks or burnouts in the cover or rotor of the ignition distributor or dirty surfaces. You can verify the presence of this defect by replacing the ignition distributor with a known good one.
Ignition switch
The operation of the anti-theft device and the correctness of the contact closure in different key positions are checked (Table 13). The table shows the contact closure for a switch with a contact part used before 1986. Since 1986, a contact part has been installed that has one common contact 15 instead of contacts 15/1 and 15/2, which closes with contact 30/1, and there is no contact P. Voltage from the battery and generator is supplied to contacts 30 and 30/1. The free INT plug is intended for connecting a radio receiver.
The locking rod of the anti-theft device extends after turning the key from the "Parking" position to the "Off" position. When installing the contact part in the switch housing, position it so that plugs 15 and 30 are on the side of the locking rod, while the wide protrusion of the contact part enters the wide groove of the switch housing.
Testing of radio interference suppression elements
These elements include high-voltage wires with a resistance of 2000±200 Ohm/m distributed along their length and a noise-suppressing resistor in the ignition distributor rotor with a resistance of 5000-6000 Ohm. Check the serviceability of these elements with an ohmmeter. In addition, a noise-suppressing capacitor is installed on the generator, the testing of which is described in the section "Generator". In a contactless ignition system, high-voltage wires of the PVPPV-40 type can be installed (blue color) with distributed resistance (2550±270) Ohm/m or PVVP-8 wires (red color) with a resistance of (2000±200) Ohm/m, as well as FE65PR or FE65CPR spark plugs with a 4-10 kOhm noise suppression resistor.