We independently change the ignition coil on the VAZ 2107

If the ignition coil on the VAZ 2107 is out of order, it will not be possible to start the car. The only thing left for the driver in such a situation is to ask passing drivers to take the car in tow or call a tow truck. And when he gets to the garage, the driver can replace the ignition coil on his own. Let's figure out how this is done.

The purpose of the ignition coil on the VAZ 2107

The ignition coil is a key component of the machine, without which the ignition of the air-fuel mixture in the combustion chambers is impossible.

The main device, without which the VAZ 2107 will not start - the ignition coil

The standard voltage of the VAZ 2107 electrical network is 12 volts. The purpose of the ignition coil is to increase this tension to a level at which a spark is generated between the electrodes of the spark plugs, which will ignite the air-fuel mixture in the combustion chamber.

Ignition coil design

Almost all ignition coils on VAZ cars are conventional step-up transformers equipped with two windings - primary and secondary. A massive steel core is located between them. All this is housed in a metal case with insulation. The primary winding is made of lacquered copper wire. The number of turns in it can vary from 130 to 150. It is to this winding that the initial voltage of 12 volts is applied.

The design of the ignition coil on the VAZ 2107 cannot be called complicated

The secondary winding is on top of the primary. The number of turns in it can reach 25 thousand. The wire in the secondary winding is also copper, but its diameter is only 0.2 mm. The output voltage supplied to the candles from the secondary winding reaches 35 thousand volts.

Types of ignition coils

Over the years, different types of ignition coils were installed on VAZ cars, which differed in design:

• common coil. One of the earliest devices that was installed on the very first "seven". Despite its venerable age, the coil is installed on the VAZ 2107 today. The design of the device was described above: two copper windings over a steel core;
• individual coil. It is mainly installed on cars with electronic ignition systems. In these devices, the primary winding is also located inside the secondary, however, individual coils are installed on all 4 VAZ 2107 plugs;
• paired coils. These devices are only used on vehicles with electronic ignition systems. These coils differ from all the others by the presence of double wires, thanks to which the spark is fed not into one, but immediately into two combustion chambers.

Location and connection diagram

The ignition coil on VAZ 2107 cars is located under the hood, near the left mudguard. Mounted on two long hairpins. A rubber cap with a high-voltage wire is connected to it.

The ignition coil on the VAZ 2107 is located under the hood on the left, near the mudguard

The coil is connected according to the diagram below.

The connection diagram of the VAZ 2107 ignition coil is not particularly complicated

On the choice of ignition coils for the VAZ 2107

VAZ 2107 cars of the latest releases are equipped with contact ignition systems, in which a domestic-made B117A coil is used. The device is quite reliable, but every part has its own service life. And when the B117A fails, it is quite difficult to find it on sale.

Standard coil VAZ 2107 - B117A

For this reason, motorists prefer to install the 27.3705 coil. It costs more (from 600 rubles). Such a high price is due to the fact that the coil 27.3705 is filled with oil inside, and the magnetic circuit in it is of an open type. It is this device that is recommended to be used when replacing a burned-out coil.

Coil 27.3705 - oil-filled, with open core

Here, the third option should also be noted: coil 3122.3705. There is no oil in this coil, and the magnetic circuit is closed. Despite this, it costs more than 27.3705 (from 700 rubles). The 3122.3705 reel is as reliable as the 27.3705, but given its overpriced price, most car owners opt for the 27.3705. Foreign coils are not installed on the VAZ 2107.

The main malfunctions of the VAZ 2107 ignition coils

If the driver, after turning the ignition key, clearly hears that the starter is rotating, but the car does not start at the same time, then most likely the ignition coil is out of order. It should be noted here that the engine may not start for other reasons: due to problems with the spark plugs, due to faults in the fuel system, etc. You can understand that the problem is in the ignition coil by the following signs:

• there is no spark on the spark plugs;
• there is no voltage on the high-voltage wires;
• various defects are visible on the coil body: chips, cracks, melted insulation, etc.
• when opening the bonnet, it clearly smells burnt insulation.

All these signs indicate that the ignition coil has burned out. As a rule, this is due to a short circuit in the turns in one of the windings. The insulation that covers the wires in the winding is destroyed over time, adjacent turns are exposed, touch and a fire occurs at the place of their contact. The winding melts and becomes completely unusable. For this reason, the ignition coils cannot be repaired. All a car enthusiast can do with a burned-out coil is to replace it.

Video: faulty ignition coil

IGNITION COIL VAZ AND ITS POSSIBLE FAULTS

Self-check of the ignition coil

To independently check the health of the ignition coil, the car owner will need a household multimeter.

Check sequence

1. The ignition coil is removed from the vehicle. All wires are removed from it.
2. Both contacts of the multimeter are connected to the primary winding of the coil. Winding resistance is measured. Example: at room temperature, the resistance of the primary winding on the B117A coil is 2.5 - 3.5 ohms. The primary winding of coil 27.3705 at the same temperature should have a resistance of no more than 0.4 ohms.
3. The multimeter contacts are now connected to the high voltage outputs on the secondary winding. The secondary winding of the B117A coil at room temperature should have a resistance of 7 to 9 kΩ. The secondary winding of the coil 27.3705 must have a resistance of 5 kOhm.
4. If all of the above values ​​are respected, the ignition coil can be considered serviceable.

Video: we independently check the health of the ignition coil

Checking the ignition coil B 117 from VAZ

Replacing the ignition coil on a VAZ 2107 car

To replace the coil, we need the following tools:

• new ignition coil;
• socket heads for 10 and 8 with a knob;
• flat screwdriver.

Coil replacement sequence

1. The hood of the car is opened, both terminals are removed from the battery with an open-end wrench for 10.
2. The main high-voltage wire is removed from the coil. This is done manually by pulling the wire up with a little effort.
   

   To remove the high-voltage wire from the VAZ 2107 coil, just pull it
3. The coil has two terminals with wires. The nuts on the terminals are unscrewed with an 8 socket, the wires are removed.
   

   The terminals on the VAZ 2107 coil are unscrewed with a socket head by 8
4. Access to the two fixing nuts of the coil is opened. They are unscrewed with a 10 socket wrench.
5. The coil is removed, replaced with a new one, after which the car's ignition system is reassembled.
   

   After unscrewing the fasteners, the ignition coil of the VAZ 2107 can be removed

So, replacing the ignition coil is not a super difficult task and even a novice driver is quite capable of doing it. The main thing is to follow the above sequence of actions, and before starting work, do not forget to remove the terminals from the battery.