VAZ fog lights. Why the fog lights of the VAZ 2114 do not work

No matter what anyone says, the headlights on domestic VAZs leave much to be desired. The VAZ 2114 is no exception; the headlights shine disgustingly in the twilight and at night, so you have to additionally use the light of fog lights or, as they are also called, PTF. However, it often happens that the PTFs do not work, and in order to quickly find the reason for the failure of fog lights on a VAZ 2114, we suggest that you familiarize yourself with the main reasons for the failure of fog lights.

Oxidation and failure of fuses

Each fog light has a separate fuse with a rating of 7.5 A in the block they are marked as F8 and F9. However, during installation, some owners install fuses near the fog lights themselves or near the relay. So if you don’t find them in the fuse box, this does not mean that they are not there. And another important point: if two fog lights do not work at once, in this case the version with a fuse is no longer necessary, because two fuses cannot blow out at the same time. Also, in some cases, cleaning the contacts of the fusible element from oxidation helps solve the problem.

Useful video

You can glean additional interesting information from the video below:

If all of the above reasons have been checked, and none of them have been identified, then the problem is in the wiring itself. In this case, you should ring all the wires used in the fog lamp connection circuit, and also check the correctness of the connection itself.

This can be done using the diagram given at the beginning. In this case, special attention should be paid to the correct connection (to the required connectors) of the button and relay.

The lamps in the PTF are burnt out

Most often, the cause of a non-working fog light on a VAZ 2114 is a burnt-out lamp. In this case, it is necessary to remove the lamp from the PTF housing and carry out a visual inspection. If at the same time you find a burnt-out lamp spiral, therefore, it is necessary to replace the lamp with a new one. There are also cases that upon visual inspection the lamp may not be burnt out. In any case, you need to insert and check another working lamp. Since in a situation with a fuse, two lamps cannot burn out at the same time, so if both VAZ 2114 fog lights do not work, the reason is different.

PTF connection diagram

But sometimes it happens that the PTFs refuse to turn on, and either one or both headlights may not work. There can be many reasons why the fog lights on a VAZ 2114 do not light up, but the main one is the appearance of oxides or corrosion in important places in the electrical circuit leading to the headlights.

Before considering all possible causes in more detail, you should familiarize yourself with the schematic diagram of connecting fog lights to the vehicle’s on-board electrical system.

It looks like this:

It contains the following symbols:

pink rectangles 10A - 10-amp fuses;
F1 and F2 - fog lights;
grounding icon - connection to ground;
+12V — output to the “+” terminal of the battery.

PTF relay does not work

The VAZ 2114 PTF is turned on through a relay that is installed in the fuse box or in another place that was selected by the electrician when installing the foglights independently. You can check the serviceability of the VAZ 2114 fog lamp relay by turning on the PTF button. If you hear a click inside, then the relay is working; if not, replace it

PTF power button does not work

The fog light switch may also be the reason why the fog lights are not working. Replacing the VAZ 2114 PTF on and off button is quite easy.

Installation of electrical equipment and fog lights on the VAZ-2114

General view of fog lights

In order to understand why the fog lights failed, you need to know a little about how the electrical equipment of the car as a whole works, as well as the connection diagram for this unit in the general electrical circuit.

So, let's look at the basic electrical equipment diagram of the VAZ-2114:

General diagram of the vehicle's electrical equipment including PTF

And also, diagrams for direct connection of fog lights.

Connection diagram to the PTF on-board network

Visual connection diagram for PTF

Reasons for failure

Now that all the electrical connection diagrams for the fog lights have been disassembled, you can proceed directly to determining the reasons for their inoperability or failure:

Fuse blown.
The light bulbs burned out.
Oxidation of contact connections.
There is no contact to ground.
The button doesn't work.
No power.
Incorrect connection.
Relay is broken.

PTF lamps do not light up (troubleshooting methods)

Now that all the reasons have been identified, we can proceed directly to considering the issue of solving the problem. For diagnostic operations you will need a tester, but for repairs you will need a set of screwdrivers, keys and some spare parts.

Now, let's look at how problems need to be solved in different cases.

Fuse blown

Fuse diagram in the mounting block

The most common problem among electrical equipment. A blown fuse breaks the electrical circuit, but at the same time protects the parts from a short circuit. It is worth noting that each headlight has its own fuse, so you need to check those marked F8 and F9 . The nominal current passing is 7.5A .

If both fog lights on the car go out at once, then you don’t have to go into the mounting block and it’s a different problem.

Burnt out light bulbs

Another common reason for fog lights not working is the bulbs burning out due to a short circuit or natural wear and tear.

New PTF lamp and socket close up

To check the serviceability of the part, we install a new lamp in the seat, and if it lights up, then the matter is definitely a failure of this particular element. As in the previous case, two lamps cannot burn out at once.

Oxidation of contact connections

Due to poor sealing, the PTF contact has oxidized

Often, another problem is that the connectors connecting the fog lights directly to the headlights become oxidized and do not make proper contact, which can cause flickering or loss of light.

In this case, the treatment method is to clean the contact group of the connectors.

No contact to ground

Ground wire from battery

The reason for the failure of the fog lights is that there is no reliable contact to ground.

This is due to the fact that the wire is exposed to the open air and is exposed to external factors, which can lead to corrosive damage. So, the method of treating a malfunction is to strip the contact connection between the wire and the ground.

The button doesn't work

During operation, the internal elements of the shutdown button are subject to wear and tear and may fail. Therefore, another step in diagnosing fog lights that are not working is the button. In this case, both headlights will not work. There are two ways to diagnose the malfunction: test the button connections with a multimeter for resistance, or install a new button and try to turn on the headlights.

Fog light switch

There is no power to the PTF chip

A faulty electrical wiring or broken wire, especially in winter, may prevent the fog lights from receiving power. In order to identify and eliminate malfunctions, you must be guided by a special wiring diagram, which is presented below.

Diagram for checking power supply of fog lights

Incorrect connection

This malfunction usually occurs when a motorist has connected the fog lights himself, but has incorrectly connected the wires to a relay or button somewhere.

To eliminate the cause of the malfunction, it is necessary to check all connections according to the PTF wiring diagram and the general electrical diagram of the vehicle.

Broken relay

In order for everything to work correctly, as in the case of headlights and brake lights, the fog lights are connected via a relay . Of course, it does not last forever - the direct current that runs through the contacts, as well as short circuits in the on-board network, can damage this element.

PTF installation kit, relay marked with arrow

Diagnostics is carried out by analogy with a button. It is necessary to either ring the contacts or install a new relay, and then check the functionality.

Failure of the fog lights themselves

The reflector is trash!

Let's look at the picture above. Since the reflector is already worn out, its “shards” penetrate into the headlight and “harm” the lamp itself. In this case, the lamp will burn out very often, and if the second headlight is in the same condition, then both will burn out at once! And the owner will be looking for the shorty!

Therefore, try to pay attention to the condition of the PTF itself.

The main causes of PTF malfunction

The most common reasons why the VAZ 2114 fog lights do not work are as follows:

fuse is blown;
burnt out light bulb(s);
oxidation of contacts occurred;
lost contact with the “mass”;
the button is faulty;
the relay has failed.

In addition, some other, rarer reasons are possible, which we will also consider below.

And so, the very first and most common reason is a blown fuse.

Each of the fog lights has its own fuse, namely F9 and F8 in the block, each of which is designed for a maximum current of 7.5 Amperes. In some cases, it happens that there are no fuses responsible for protecting the fog lights in the common block.

This happens when a car is purchased second-hand, and the PTFs were installed independently by its previous owner. In this case, you should inspect the entrance and the board on which the headlights themselves are located. Very often, during self-installation, the fuse is attached in this place.

When replacing, you should use a fuse exclusively for a current of 7.5 A. A fuse designed for a higher current simply will not be able to protect the headlights from a voltage surge, and one designed for a lower one will often burn out.

If both fog lights do not light up at once, then the problem is most likely not in the fuse, since the failure of two protective elements at once is quite rare.

The next reason why the fog lights on the VAZ 2114 do not light up may be the usual burnout of the light bulbs. In order to check this, just unscrew the old lamps and screw in new ones in their place.

Another, no less common reason (especially in the middle climate) is the oxidation of the contact connectors of the headlights themselves. Very often this causes blinking or intermittent operation of the light bulbs. In order to eliminate this nuisance, it is enough to remove oxides by cleaning the headlight contacts with fine-grain sandpaper or wiping well with WD-40, White Spirit or kerosene.

Also, the contact running from the battery negative to the housing (to ground) often oxidizes. If this happens, the joint should be thoroughly cleaned, as described above.

Another reason why the fog lights may not turn on is the failure of the button located on the front panel of the car, which is used to turn on the PTF. You can check its functionality in two ways: connect a new button (if you have one) and try to turn on the headlights, or ring the button with a multimeter. If the button turns out to be damaged, it should be replaced with a new one, since it is practically not repairable.

Failure of the relay may also be the reason why the rear fog lights of the VAZ 2114 do not work. It is checked in the same way as a button - by testing the contact legs or replacing the relay with a new one. If it turns out that it has become unusable, it should also be replaced.

Often the cause of headlight failure can be the headlights themselves. During long-term use, the reflective layer can be destroyed, chipped and fall on electrical elements, thereby interfering with their proper operation. That is why it is worth periodically checking the internal condition of all headlights (not just PTF).