© Mikhail Ukhanov, aka miha
The ignition module belongs to the groups of actuators, the operability and “diligence” of which is not checked and monitored in any way, because there is no feedback and the ECU simply sends control signals to them. Diagnostics of the MI can be done by the computer only indirectly. And on the performance of the MI, and the ignition module, in particular, the normal operation of the engine depends. Another catch is that the performance of the modules is very relative. like any other IM, it can have not two stable states working / not working, but much more intermediate, “semi-working” states in which the car “seems to work, but not like necessary. ” For example, the Ministry of Health can “mope” only at certain speeds, at a certain temperature.
Therefore, the question arises of a quality and unambiguous verification. In the Rostov car service “Injector” Mikhail Ukhanov (aka miha) and Tom (aka Igor Semenov) developed his own version of the device for checking ignition modules, which allows this to be done.
The technique is quite simple if you understand the essence of the process. We have a generator with a variable frequency, on average from 3 to 30 Hz. and a variable output pulse duration, from 1 to 5 ms.
A fully functional module (one channel) is capable of delivering 13 mm to a spark gap. a full spark, with a core accumulation time of 2 ms., naturally, on a charged battery about. 12, 6 v.
If the coil has a clear inter-turn breakdown, there will be no spark on the spark gap or there will be an intermittent one.
If the breakdown is insignificant or there is a breakdown of the insulation to ground, as well as a wire with a break or a large resistance, we have in mind a normal spark, but if we alternately close the ends of the arrester with a probe placed on the ground (in this case, the MZ must be installed on the machine), the spark it will disappear or become intermittent (since it will go to ground through places where insulation is broken (through the MZ casing), sometimes an external breakdown of the coil through a crack on the casing is visible.
If we close one end to ground, the energy of the coil with good insulation will reach the spark gap and we will see a spark, and if there is a defect, then, as you know, electricity will go through the least resistance, in this case the spark will slip anywhere before reaching the spark gap.
In the photos below. how it all works. By the way, my 12.ka turned up.
Video: Ignition Coil Adjustment On Homlight Trimmer
There is nothing complicated, with a certain skill the modules and coils are rejected at a time.
With the accumulation time and the gap on the arrester, you can experiment and develop your own technique, this is not important, the main thing is that you understand the essence of the process.
Another method of application is much more interesting. the search for cracks and breakdown on wires of 16 cells. engines and, especially, on the Volga. The technique is simple to disgrace, but it makes a lasting impression on customers. We feed a larger frequency to the coil, and the maximum accumulation time (in order to break through, if possible, a weak spot); we catch one contact of the arrester on the ground (!), at this moment with a second probe, also fitted on the ground (!), draw along the surface of the cap, dressed on the second contact of the arrester, wire or coil, and if a defect occurs, we see a distinct arc in place of breakdown.
Scheme of the tester based on the control board of the MOH from Mikhail Ukhanov: download.
How to connect a coil
The ignition coil is a transformer whose operation is aimed at increasing direct current. Its main task is the generation of high-voltage current, without which the arson of the fuel mixture is not possible. The current from the battery enters the primary winding. It consists of one hundred or more turns of copper wire, which is insulated with a special substance. A low-voltage voltage (twelve volts) is supplied to the edges. The edges are connected to the contacts on its cover. On the secondary, the number of turns is much larger (up to thirty thousand) and the wire is much thinner. On the secondary, a high voltage is created (from twenty-five to thirty thousand volts) due to the thickness and number of turns.
It is connected as follows: the secondary circuit contact is connected to the primary negative terminal, and the second winding contact is connected to the neutral terminal on the cover, this wire is the high voltage transmitter. A high voltage wire is connected to this terminal, the other end of which is connected to the neutral terminal on the cover. To create a large magnetic field, an iron core is located between the windings. The secondary winding is located inside the primary.
Structurally, the ignition coil consists of the following elements:
- Insulating paper;
- Winding (primary and secondary);
- Insulation material between windings;
- Primary winding terminal;
- Pin screw;
- The terminal is central;
- Output terminal on the primary and secondary windings;
- Spring central terminal;
- Primary winding frame;
- External insulation on the primary winding;
- Mounting bracket;
- External magnetic core and core.
So, briefly about the principle of work.
A high voltage current arises on the secondary winding, and at this moment a low current passes on the primary. Thus, a magnetic field arises, as a result of which a high voltage current pulse appears on the secondary winding. At the moment when it is necessary to create a spark, the contacts of the ignition interrupter open, and at this moment the circuit on the primary winding opens. A high voltage current is supplied to the central contact of the lid and rushes into the contact near which the slider is located.
When connecting the coil to the ignition system of the car, in principle, you should not have any difficulties in the case when during the preliminary dismantling you indicated or remembered which wires are connected to where. If you have not done so, then I will tell you how to do it. The connection is as follows: the brown wire must be connected to the positive terminal. Usually, the positive terminal is indicated by “”, but if you do not observe the sign, then you need to find it yourself. You can use an indicator screwdriver for this. I think that you know how to use it. It is important that before connecting, clean all the contacts and check the wires for proper operation. The black terminal is connected to the second terminal (terminal “K”). This wire is connected to a voltage distributor (distributor).
A diagram of a bunch of several elements is as follows. One of the coil ends is connected to the on-board network. The second end connects to the next, and thus connects each to the last. The remaining free contact of the last coil must be connected to the distributor. And a common point is connected to the voltage switch. After all the fixing bolts and nuts are tightened, the replacement can be considered completed.
A few important tips before replacing and connecting. In the case when you have determined for yourself that the coil is the problem of the ignition malfunction, it is best to immediately purchase a new one and connect it (the circuit is indicated above). So you will be sure that now there are no problems with it, since it is completely new.
If you find some defects on the surface, it is better to replace it immediately. Otherwise, it will work for some more time and you will again have to return to this topic. It is better to play it safe in advance so as not to stop somewhere on the road. After all, ignition of a car requires not forgiving mistakes and negligence.
During car repairs, especially when it comes to the ignition system, you must be extremely careful in actions. Since you can run into high voltage wires. Therefore, when replacing or performing repairs, safety precautions must be observed.
Video “Ignition Coil Connection Diagram”
The recording shows how you can independently connect the coil.