The oil pressure light comes on: the main reasons. How to fix the problem if the pressure light is on?

How does the oil sensor work and why can it fail?

Let's consider the situation if you are on the road and the low pressure indicator has triggered.
The very first thing you need to do is stop the vehicle and turn off the engine. As soon as it cools down, you will have to check the lubricant level in the system. There is a special dipstick under the hood for this purpose. It is wiped dry and immersed in its original place. It is quite possible that the level will be below the minimum level. This means that somewhere there is a leak or depressurization of connections. You can set off again only after adding oil to the engine. If the lamp continues to light after starting and does not go out subsequently, it makes sense to think about towing the car to the nearest service station or to a trusted auto mechanic. The matter may turn out to be quite serious, so it is advisable to conduct the examination in a calm environment. Since we have already said that the causes of low pressure may be associated with a faulty sensor, it would be useful to understand the principle of operation of this device. There are certain contacts inside it. Until the ignition is turned on, there is no pressure in the system, so the contacts are closed. When you turn the key and turn on the ignition, but before the starter starts, the warning lamp should be on. If this does not happen, then there may be some kind of malfunction. Maybe the light bulb itself simply burned out, or maybe the contacts were broken or the sensor itself failed. As soon as we start the engine, the contacts open, leading to the light bulb going out.

The oil pressure light comes on at idle: ways to check

The red light, marked on many cars with the image of an oil can, was added to the dashboard for a reason. It is connected to a common electrical circuit with a sensor mounted in one of the channels of the engine lubrication system. When the element detects a pressure drop below a critical level, the circuit closes and the lamp flashes red, informing the driver of an emergency malfunction.

The signal from the red lamp with the image of an oil can indicates a malfunction of the engine lubrication system

The purpose of the emergency lamp is to warn the car owner in time about the engine's oil starvation. If for various reasons it does not light up or the driver ignores the red “oil can” signal on the instrument panel, then the following consequences may occur:

due to lack of lubrication, the crankshaft journals wear out, the sliding bearings (liners) may rotate and eventually jam;

As a result of oil starvation, wear develops on the crankshaft journals.
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In the absence of oil, the piston skirts will overheat and expand in volume, leaving scratches and scuffs on the cylinder walls;

A poorly lubricated piston heats up and leaves marks on the cylinder wall
the camshaft bearings located at the highest point of the engine will fail;

Without lubrication, camshaft bearings quickly fail
the service life of the remaining rubbing parts will be sharply reduced.

Insufficient amount of lubricant or its absence in any case leads to breakdown and costly repair of the power unit. A timely signal on the dashboard will help avoid this.

The indicator light on the dashboard reacts strictly to engine oil pressure. Due to the level being reduced within reasonable limits, the signal will not appear on the panel. The exception is the loss of 2/3 of the lubricant when the oil intake of the pump begins to pick up air and crankcase gases. Then the pressure in the lubricating channels will inevitably drop, to which the sensor will react and the light will light up.

The oil receiver is specially installed at the bottom of the pan so that the system operates when there is a lack of lubrication.
The circuit that signals problems with the lubrication of the power unit consists of parts that also periodically break. So a flashing lamp does not always mean fatal engine failure. But if it lights up on your car, then you need to act like this:

Stop moving.
Turn off the engine.
Check the lubricant level and add up to normal if necessary.

The lubricant level in a car engine is checked with a special dipstick
Topping up did not work - transport the car to the garage or to a car service using a tow truck or in tow.
If the indicator light is intermittent (flashing), then move to the repair site under your own power at low speed. Monitor the coolant temperature gauge and pressure light: when it stops flashing and lights up, immediately turn off the engine.

In your garage, you can find the cause of the alarm if you follow the steps below.

Continuous light or blinking of the indicator indicates that the oil pressure in the engine is below acceptable standards. In old cars, a special analogue display was installed on the dashboards, displaying the d.m. in the motor, where the current level was shown in units of measurement.

If the indicator lamp lights up when the engine is idling, then you need to find the source of the malfunction and neutralize it as quickly as possible.

You can contact your nearest service station for help or try to find and fix problems yourself.

To find out how much lubricant is in the internal combustion engine at the moment, you need to do the following: turn off the engine, open the hood and check the oil dipstick in the engine to measure the oil level.

There are special marks on the dipstick that show the degree of immersion in the lubricant. If the level is low, this can be seen by the corresponding mark, in which case it is necessary to add oil.

Sensor check

To check, the engine is started and warmed up, the gas is squeezed out in neutral until the crankshaft speed reaches approximately 1000-1100 rpm.

If the indicator goes out when the gas is released, the sensor may be faulty. To be sure, you can remove it and replace it with a pressure gauge to measure the pressure. If the measurement values are below the norm, then the sensor alerts are correct; if they correspond to the norm, it is faulty and must be replaced.

High-quality lubricant in internal combustion engines has good viscosity. It can be checked by carefully inspecting the oil dipstick and also removing the oil pan.

If the oil is very thin, then the time has come for its replacement or it has been missed altogether. The use of diluted lubricant, essentially waste, is harmful to the engine and leads to its rapid wear. It is recommended to change the oil exactly as scheduled.

If, after changing the oil in the engine, the indicator lamp continues to blink for more than 10-15 seconds at idle speed, then this may indicate a faulty filter. Breakage/clogging of a part is determined visually.

To determine the condition of the oil pump, it is necessary to remove the oil pan. It is quite difficult to do this on your own, in particular on foreign car brands. Therefore, if you suspect that the oil pump is faulty, it is better to contact a car service center for qualified diagnostics.

Engine wear

If the engine has a high mileage, the oil lubricant may leak out, as a result of which the pressure will decrease. Long service life and old internal combustion engine parts cause rapid oil consumption, which can be evidenced by atypical noise in the engine and blinking indicator light. The solution to the problem may be replacing worn-out parts with new ones or a complete overhaul of the engine.

To summarize, it is worth noting that driving with a glowing oil pressure indicator is unsafe and can lead to serious car repairs, including a complete engine replacement.

Ignoring malfunctions signaled by the light sensor will inevitably lead to breakdown of the entire internal combustion engine mechanism. Therefore, experts recommend immediately identifying the malfunction and fixing it yourself or at the nearest car service center.

If the oil pressure is on, then you will definitely have to repair the engine. It doesn’t matter what the reason is, in any case it is quite serious. Typically the scenario is like this:

As a rule, everything starts after changing the oil, especially if this is done irregularly. The thing is that old oil has a slightly higher viscosity, thanks to all the debris and deposits that are mixed with the lubricant. Yes, this slurry also contains abrasive particles, they only aggravate the situation. After new oil has been added, it flushes all the lines, all channels, including the channels in the crankshaft that are needed to supply oil.
The gaps, which were slightly compensated for by debris, increase, and then everything goes in the same sequence as described above. The oil pressure flashes first at idle or when the engine is hot. This is due to low pump speeds and a decrease in oil viscosity with increasing temperature. At this stage there is still time to escape with little blood. This means that the oil pressure when cold is still normal, and accordingly, the parts are still in a more or less alive state.
Then the oil pressure is on at idle and when the engine is warm. All is not lost here either. Yes, the parts are already very worn out, but, as a rule, they are still subject to repair.
Then the oil pressure light comes on when cold. Now is the time to sound the alarm.

In general, as soon as the oil pressure light comes on, you should immediately turn off the engine and begin diagnostics, and then, possibly, repairs.

First of all, it’s worth understanding that you can’t take anyone’s word for it, much less the oil pressure sensor. Some older cars have two sensors, one for the hazard warning light and one for the pressure gauge.

Audi and Volkswagen cars of the 90s use a pressure monitoring system with two sensors and warning lamps. One pressure warning lamp lights up when the pressure is critically low, and the second when the pressure is critically high.

We take a regular analog (dial) pressure gauge. We connect it instead of the pressure sensor. This can be done using an old gutted sensor to which you connect a hose.

We take a regular analog (dial) pressure gauge. We connect it instead of the pressure sensor. This can be done using an old gutted sensor to which you connect a hose.
We start the engine and look at the pressure. It should be no lower than 0.2 MPa and no higher than 0.8 MPa. There are a number of newer cars that use very thin oil because the pressure in the lubrication system is very high, more than 1 MPa, but there are very few such models.

After we have made sure that the oil pressure is not just on, and that there really is a malfunction, we need to check the following points. Some of them can be checked independently, while others can only be checked with special equipment.

If the oil light is on, the first thing to check is the pump. To check it, removal and disassembly are required; we will not describe how this is done, because each model has its own algorithm. Next, the gaps are measured with a feeler gauge at the points specified by the manufacturer. If they are higher than normal, then the pump is changed.
If the oil light is on, the first thing to check is the pump. To check it, removal and disassembly are required; we will not describe how this is done, because each model has its own algorithm. Next, the gaps are measured with a feeler gauge at the points specified by the manufacturer. If they are higher than normal, then the pump is changed.
Also, when the oil pressure light comes on, you need to check the crankshaft journals and the thickness of the bearings. If the necks fall within the range of required sizes, then it is enough to replace the liners. We will not describe the replacement either, since there is also a different procedure for each engine, not just for the model.

Why do you need an oil pressure lamp in a car?

When a car leaves the factory assembly line, it must have such an important detail as an oil pressure lamp, which informs the driver about the lack of lubrication in the engine. As soon as the “oil can” icon lights up on the instrument panel, you need to be concerned about a possible lack of oil in the engine. It is not necessary to immediately go to a car service center, first you need to identify the cause yourself, perhaps it is not so complicated and scary.

There may be several reasons for the light coming from the pressure sensor to light up:

Signs and causes of oil pressure sensor malfunction

Identifying a defective sensor is quite simple. This is indicated by the presence of the following factors:

Problems when starting the engine.
After turning on the ignition, the Check Engine light comes on and flashes, as well as the oil icon. Goes off after starting the engine.
The engine slowly increases speed and its power is lost.
The car jerks while driving.
Acceleration is difficult.

The sensor may become unusable as a result of:

failure of the oil pump;
clogging of the controller with waste material;
insufficient lubrication level in the system;
oil filter contamination;
damage to the sensor membrane;
short circuit in the wiring in the oil pressure sensor circuit;
rheostat wear.

To increase the service life of the sensor, as well as other units and components of the car, it is necessary to fill only high-quality oil from a trusted manufacturer.

Reasons for the oil pressure warning light to come on

So, the warning light usually lights up after starting the engine or when it is idling. There may be several reasons for this phenomenon, but the main thing is to understand and accept for yourself that this should be a signal that there is some kind of malfunction. Therefore, you need to take appropriate measures so as not to worsen the situation. In any case, if the lamp blinks, it means that you need to identify the malfunction and do everything to eliminate it as soon as possible.

Basic reasons

The vehicle's warning lamps are controlled by the on-board monitoring system (OBS). It is designed to notify the driver of malfunctions or malfunctions of vehicle systems using these same light bulbs. In addition, the BSK is responsible for indicating turn signals, turning on high beams, rear fog lights, signaling the parking brake is applied, and so on.

The oil pressure and level light is also controlled by the on-board control system. On modern cars these are two different indicators, but on older cars there is one that lights up when the engine oil pressure in the crankcase is low.

This light bulb looks like an oil can. It lights up yellow when the oil level is below normal, and red when the pressure in the system has dropped. On some modern cars, instead of an indicator, the corresponding inscriptions are displayed on the on-board computer.

Both lights can light up independently of each other because they receive data from two different sensors.

Let's look at the reasons why the oil level/pressure lights may come on.

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The oil level in the crankcase is below the specified level

This problem is both the simplest and the most terrible. During operation, any engine consumes one or another amount of engine oil. Therefore, if the amount of missing fluid falls within normal conditions, then it will be enough to simply replenish the oil level.

The worst thing is when the reason for the drop in oil level is insufficient sealing of the engine or the oil leak is caused by a serious malfunction.

When the oil level is below the required level, the pressure sensor sends a signal to the electronic control unit, which notifies the BSK about the problem. Accordingly, the light on the dashboard is activated. In this case, the lamp itself does not blink, but is constantly on. This can happen both at idle and while driving, on a hot or cold engine, etc.

The oil pressure light also comes on when the ignition is turned on, but after starting the engine, if there are no problems, it goes out. In addition, it can turn on during ascent or descent, when engine oil collects in one part of the crankcase, leaving the other dry. If there are no faults, it will go out when the car is leveled.

If, after starting the engine or leveling the car after lifting/lowering, it continues to burn, you need to go to a car service center and find out the reason.

Using oil of the wrong viscosity

This problem is especially relevant in the winter season. If engine oil thickens at subzero temperatures, it is harder for the pump to pump it. Accordingly, the pressure turns out to be insufficient, which is recorded by the corresponding sensor.

Oil filter problems

There is always some amount of engine oil in the oil filter. This is necessary so that there is no oil starvation when starting the engine. Therefore, the design of the filters may include a check valve or a locking washer that retains the lubricant when the internal combustion engine is turned off.

But on low-quality filters, such components are either completely absent or do not cope with their task. Thus, the oil flows back into the oil pan. Accordingly, after startup, when the power unit gains pressure, it experiences oil starvation, which leads to increased wear. In this case, the indicator lights up for a few minutes and then disappears.

But a clogged oil filter causes much more problems. It not only creates additional stress on the oil pump, but also helps reduce pressure in the system.

Sensor malfunction

If the oil level sensor is faulty, the light will remain on constantly. Most often this happens because its slider is stuck or another breakdown has occurred, which depends on the design of the sensor. The same is true for the oil pressure sensor.

Oil pump malfunctions

Depending on what type of oil pump your vehicle has, the reasons why it fails will vary. In this case, the oil pressure light will be constantly on or flashing.

But if the oil filter mesh is clogged, then the signs are exactly the same as with a clogged filter. In addition to the fact that contamination leads to a decrease in oil level and pressure, it forces the oil pump to work harder to pump oil through the system.

Engine malfunctions

Let's talk about the most dangerous reasons. All of them are related to the condition of the engine and its specific components.

The most common reason why pressure and oil level lights come on is a leak. Most often, lubricant escapes through leaking gaskets and O-rings, pipes, oil lines, etc.

Clogged oil passages are also the cause of light bulbs. This is especially true for foreign cars where the engine oil channels are quite narrow, for example, in VAG cars. Accordingly, in such machines it is necessary to use only motor oils and high-quality fuel recommended by the manufacturer.

Wear of the cylinder-piston group of the internal combustion engine also leads to a drop in oil level and pressure. In this case, adding lubricant will help only for a short period of time, because oil consumption for waste will increase significantly. This problem can only be solved through a major overhaul of the power unit.

Antifreeze or gasoline getting into the engine oil

This usually indicates a failed cylinder head gasket. Externally, this is expressed by a constant drop in the coolant level without visible leaks, the appearance of white smoke from the exhaust pipe, the presence of a smell of fuel or coolant from engine oil, the formation of an emulsion, etc.

There are situations when the engine oil level is normal, but the oil pressure lamp is still on. In this case, the cause may be a poor-quality or clogged oil filter, a faulty oil pump, or antifreeze or gasoline getting into the lubricant.

Winter problems

Often, when starting the engine in frosts of -20 or more, the oil pressure lamp does not go out for a long time. The most common reason for this is poor quality oil. At this temperature, the lubricant thickens greatly and prevents the sensor from functioning normally. After a couple of minutes of engine operation, the lubricant becomes more liquid and the signal disappears, the sensor begins to work normally.

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Rare causes of oil light activation

There are a number of other unlikely reasons why the oil light on the dashboard may come on. In particular:

Faulty wiring and/or vehicle ECU. In the first case, for example, the insulation of individual wires may be damaged, causing a false signal to be sent through the wiring to the light bulb. However, in most cases, this situation is monitored by the electronic control unit and it will automatically notify the driver about such a breakdown through the Check Engine lamp (for this you need to have an error scanner such as ELM 327). As for the ECU, this could be a banal “glitch”, that is, a computer program failure. However, this happens extremely rarely, and it makes sense to check the control unit if there are other, more complex, breakdowns. Sometimes you can find information on forums that the cause may be poor-quality soldering of one or more tracks of the control unit. Accordingly, they need to be re-soldered, but for this it is better to seek help from a car service center that has the appropriate equipment and qualified personnel.
The oil filter was not changed during the oil change. In particular, this may cause the light to come on after an oil change. Remember that the filter must be changed when replacing the lubricant. If you have driven very little after the corresponding replacement, then you can replace this unit with a new one. If the mileage is already quite large, then it is better to change the oil again and this time together with installing an oil filter. A similar situation can occur if the new oil filter was not tightened tightly enough (the torque value must be observed, and you can find it in the technical documentation for the car) or is simply defective.
When starting the engine in severe frosts, the oil light may light up for the first few seconds and then go out. This is due to the fact that at low temperatures the oil becomes very thick and it is difficult for the oil pump to pump it through the system; accordingly, insufficient pressure (and often vacuum) is created in it, which is perceived by the corresponding sensor as a malfunction. However, after a few seconds/minutes, the oil regains its fluidity and the pressure in the system returns to normal; accordingly, the sensor detects this, transmits a signal to the computer, and the light goes out. Please note that you should always choose oil not only in accordance with the recommendations of the car manufacturer (usually it allows the use of oils with several similar viscosities), but also with the operating conditions of the car. In particular, we are talking about low-temperature viscosity. A similar situation can occur after the car has been parked for a long time without starting the engine (for example, several months), especially if there is old (dirty) oil in the crankcase.

Gasket failure

If the gasket under the head of the block is broken, lubricant leaks and coolant gets into it. In this case, the lubricant level will be higher than normal on the dipstick; in fact, there will be coolant underneath it.

It is determined by an increased level on the dipstick, a changed color of the lubricant, and a smell coming from under the radiator cap or expansion tank. The appearance of an oil film in the tank or radiator.

Here you immediately need to replace the cylinder head gasket, cooling fluid and oil, and you can’t continue driving such a car, water getting into the engine oil is like poison for a person, it ruins him.

As you understand, a blinking pressure light can be a harbinger of serious problems, even if everything seems to be in order with the level.

Disorder with engine parts

Clogged channels of the lubrication system will also make themselves felt by a flashing pressure light. This happens because in modern engines the lubrication channels are quite narrow. To avoid clogging of the channels, you need to use only high-quality oil and good gasoline so that it does not produce precipitation, combustion waste, and these channels do not become clogged.

Low pressure may be due to severe wear of the engine CPG, then oil pours out through the increased gaps, the pressure decreases. This reason occurs in old, worn-out engines, which are long overdue for a major overhaul.

Wiring problems

Don't forget about electrical wiring. A short circuit in it can also cause the light on the dashboard to light up. Inspect externally for melted or broken wires under the hood.

How does the oil pressure light work?

Once behind the wheel of the car, the driver turns on the ignition. He will see a red oil pressure light on the dashboard.

This means that the sensors are working properly, the wiring from the sensors to the instrument panel is intact, and the light bulbs have not burned out.

If this lamp does not light, you should invite a specialist to check the wiring leading from the sensors.

Another reason for a non-working light bulb is a burnt-out LED on the dashboard or damage to the panel itself.

In this case, you need to put all the components in order, since obviously non-working oil pressure monitoring devices can mislead the motorist.

After starting the engine, the driver will see that the oil pressure light has gone out. This is fine.

The oil pump pumps oil from the sump, it flows through the filter through channels to the rubbing parts, and fills the hydraulic compensators.

There are special sensors installed in the filter block or on the cylinder head that are activated if the oil pressure is normal.

As soon as the oil pressure drops, the sensors turn off and a light comes on on the dashboard.

This is a signal to the driver that there is a problem with the oil pressure.

Modern engines have a more complex system - there are several sensors that allow you to monitor oil pressure at any temperature range and engine speed.

If the light does not go out after starting the engine, you need to turn it off.

Working without oil can damage the bearings on the crankshaft and damage other rubbing parts.

Video: what happens if you drive 14 km without oil

What to do if the pressure light comes on?

The most reasonable solution in this situation would be to visit a car service center to determine why the warning light came on.

It is strictly forbidden to travel long distances if such a situation arises. This almost always indicates complex engine malfunctions that require immediate attention.

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If the light comes on while you're on the road, the easiest thing to do is check the oil level, because... This procedure does not require any special skills or additional tools.

How to do it:

Stop the car and turn off the engine
We wait 15-20 minutes until the engine cools down and the oil drains back into the oil pan
Checking the oil level using a dipstick
If the oil level is OK, then most likely there is a complex engine malfunction or a broken sensor
If the oil level is insufficient, then, if you have a canister with lubricant, you can add fluid and drive to a car service center without loading the engine
If there is no oil at hand, then it is best not to continue driving, but to call a tow truck or ask friends for help to get to the service station
In the worst case scenario, you will have to continue driving under your own power, but, again, without loading the engine

Determining whether the oil pressure sensor is to blame for the light coming on is also easy. To do this, it is enough to increase the engine speed to 1000-1500 rpm at idle. If the light goes out after this action, it means the pressure is normal.

In any case, all roads lead to a car service. Even if you are able to diagnose and fix the problem on your own, it would be a good idea to consult with familiar mechanics.

Remember that if the oil pressure light comes on, you should immediately seek help from a car service center. Such breakdowns are very dangerous and even with a slight delay you can end up with major repairs or, in extreme cases, engine replacement.

How to identify and fix more complex breakdowns

To determine the reasons why the oil pressure light is on, a specialist will definitely perform the following operations:

check oil pressure;
diagnoses wiring faults;
will test the condition of the sensors.

Based on the results of these operations, enough data will be obtained to determine the cause of the malfunction with a high degree of probability.

Clogged oil receiver

Oil pressure does not increase at any speed.

The breakdown can be eliminated by mechanically cleaning the oil receiver grid, for which you will have to remove the engine sump.

To do this, you need to drain the oil and unscrew all the bolts that secure the pan.

The oil receiver screen must be removed and cleaned of dirt.

Be sure to check the oil intake pipe as well.

If it is poorly screwed on or has holes, the oil pump will suck air through these leaks and the oil pressure will be low.

Video: oil intake screen clogged

Faulty oil pump or pressure relief valve

The oil pressure is low and increases slightly as the speed increases. The problem can only be resolved by replacing the oil pump.

Diagnostics of this unit is simple - you need to remove the oil pump, clamp the drive shaft into the drill chuck, lower the oil intake into a container with oil and start the drill. The oil should flow in a steady stream. Be sure to check the drill at low speeds - there is a risk of getting dirty or splashing everything around.

It is better to entrust the replacement of the oil pump to qualified auto mechanics, but if you have experience, you can do it yourself.

The engines of each car manufacturer are different, so it is advisable to carefully study the repair and operating instructions for your car before starting work.

Video: example of replacing an oil pump on an engine

With the pan removed, most engines have access to the oil pump mounting hardware.

After unscrewing all the bolts that secure the pump, carefully remove it.

We try not to damage the seals and the interface between the oil pump and the oil channels.

When installing a new pump, the main requirement is cleanliness. The presence of dirt or sand, which can lead to depressurization of the oil channels, is not allowed.

The new part should fit neatly into place, without effort or deformation.

When installing, pay attention to the alignment of the drive shaft and oil holes.

Worn crankshaft bearings

The light comes on at idle speed, and will go out as the engine speed increases.

The crankshaft will need to be diagnosed and the bearings replaced.

It is better to entrust this operation to car mechanics. They have sufficient knowledge and skills, as well as tools and access to high-tech equipment.

It is better for people without experience not to carry out work on the engine crankshaft, since the cost of a mistake is a new engine.

If you decide to check and replace the liners yourself, read the owner's manual for your vehicle. Observe all tightening torques and work order.

Diagnosis of the crankshaft is only possible if it is removed and a micrometer is available.

To remove the crankshaft, you need to unscrew the connecting rod fastenings in order from the center to the edges.

During disassembly, attention should be paid to the condition of the liners - they should be evenly worn, without scratches.

It is better to replace the inserts with new ones. In garage conditions, the crankshaft journals can only be inspected for the presence of burrs and scratches; to check the crankshaft for runout or ellipse of the journals, you need a special machine and a micrometer.

If there is wear, scuffing or scratches, the crankshaft journals are ground on a special machine, and replacement size bearings are selected.

Video: example of replacing crankshaft bearings

During installation, it is important to monitor the position of the locks.

These are special recesses that prevent the liners from turning.

The inserts must be lubricated with oil. It is necessary to monitor the correspondence of the holes in the liners and the oil channels.

After assembling the unit, it is important to tighten all bolts with the tightening torque specified in the instruction manual.

A correctly assembled crankshaft rotates by hand without excessive resistance or beating.

Oil channels clogged

If you unscrew the sensor and crank the engine with the starter, oil should come out from there.

If oil does not flow, you need to check the presence of oil, replace the oil pump with a known good one, and also blow out the oil channels with compressed air.

However, in advanced cases, clogged oil lines are almost impossible to clean.

How to check the oil pressure sensor: tips from car owners

We need a regular tester
“I know exactly what to do if the oil can catches fire. Oil pressure is controlled by an independent sensor. Its operation can be checked with a regular tester, but to do this you need to know what resistance it should produce at a certain pressure. In general, it’s easier to change it just in case there are doubts about its functionality, having first checked the wiring, etc.”
The service will check it in five minutes
“I was driving on a dirt road and hit the ground with the guard several times, after which the light came on with a sound and a stop sign.” I went for diagnostics and checked the pan, etc. for oil leaks. The service guys said that most likely the light came on because of the sensor. Today I bought Spanish for 250 rubles. and set it down without straining. It is located a little higher and to the right of the dipstick, under some kind of plastic tube. It is better to first pull out the dipstick so that it is convenient to unscrew it with a 22 wrench. What I mean is that it’s easier to go to a service center, where they’ll check this sensor in five minutes and tell you whether you need a new one or not.”
It couldn't be simpler!
“The check is carried out as follows. 0.3 bar sensor: remove the wire from it with the car running and short it to ground - the light on the dash lights up - everything is ok. We connect everything in place. 1.8 bar sensor: remove the wire from it with the car running and do not connect it anywhere. We sit in the cabin and increase the engine speed to 2-3 thousand. If the light comes on accompanied by a sound signal, we connect everything back into place. In general, everything is very simple. If at least one of the above is not fulfilled, we look for the reason why the oil can caught fire.”
You need a multimeter and a pump with a pressure gauge
“Recently, my oil light came on. I'm not new to this and can tell you exactly what to do. To check the DDM, you need to have a pump with a pressure gauge and a multimeter. How to identify a problem in the work of DDM? First you need to connect a multimeter to test the circuit. Then connect the electrodes of the device to the sensor; the multimeter should display zero resistance.
Then in this position, without disconnecting anything, you need to pump the pump, at this moment a working device should show “infinity”, since the circuit opens.”

Diagnostics of the electronic oil pressure sensor with a multimeter

An electronic pressure sensor is installed on modern cars, both foreign and domestic, including the VAZ-2114 and other new Ladas. Checking them is quite simple. When a certain pressure is reached, the electrical circuit is broken, which means diagnostics can be carried out using a multimeter.

Sequencing:

The multimeter is switched to the “circuit test” mode (you can switch to ohmmeter mode).
Then connect the air pump to the hole with the sensor sensing element and seal the joint well. This is very important, because the accuracy of the diagnostics depends on the tightness.
The first probe from the multimeter is connected to the output contact of the sensor, and the second is connected to its body (“to ground”).
Afterwards, the pump pressurizes the DDM to approximately 1 – 1.5 atmospheres. You should not pump it sharply or forcefully - you can damage the membrane, which will definitely damage the sensor. If the pressure sensor is fully operational, the electrical circuit opens almost immediately. Pressure acts on the mechanical rod through a membrane and even at low pressure breaks the chain.

If during testing the tester detects an open circuit, this indicates a working sensor. If there was no rupture, the oil pressure sensor must be replaced. Less commonly, the oil pressure light comes on due to damaged insulation or broken wiring. If the sensor is working, you should “ring” the wires from it to the ECU.

In addition, the oil pressure sensor can be checked without instruments, although the readings will not be accurate, but if you don’t have a multimeter, it will do. To do this, the power wire is disconnected from the sensor and shorted to ground. If the device is working properly, the dashboard warning light will not light up. If it lights up, it means it’s time to change the sensor.

How far can you travel if the indicator is on?

The answer to this question depends on why the lamp came on. If the indicator is active, then the first thing to do is check the amount of oil. If it is less than the established limit, and topping up is not possible, then you can drive the car 3–5 km at medium speeds at low speed to the place where the oil level is restored to normal.

You should not drive a car with insufficient lubricant in the engine. Otherwise, the engine will wear out faster and there will be a risk of complete breakdown. If the light starts flashing or stays on, try to fix the problem as quickly as possible.

Sources

https://avto-kul.ru/neispravnosti-v-puti/zagorelas-kontrolnaya-lampa-davteniya-masla.html
https://maslo.biz/interesting/zagoraetsya-lampochka-davleniya.html
https://mirsmazok.ru/motornye-masla/gorit-lampochka-davleniya-masla-osnovnye-prichiny/
https://fastmb.ru/autoremont/540-zagorelas-lampochka-davleniya-masla.html
https://osensorax.ru/remont/chto-delat-esli-zagorelas-lampa-davleniya-masla
https://topmekhanik.ru/gorit-lampochka-masla/
https://etlib.ru/blog/948-gorit-lampochka-masla
https://mojcar.ru/ustrojstva-avtomobilya/dvigatel/u-vas-gorit-lampochka-davleniya-masla-no-maslo-v-norme.html
https://rad-star.ru/pressroom/articles/zagorelas-lampochka-davleniya-masla/

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