Why does the oil pressure lamp not light up when the ignition is turned on
Content
Any car "eats" oil, although sometimes it is imperceptible. When the oil level drops to critical, the pressure also drops, as a result, the engine runs in oil starvation mode. In this mode, there is an active wear of parts in friction pairs. First of all, connecting rod bearings and connecting rod journals of the crankshaft fail. When the pressure in the vehicle's lubrication system decreases, the indicator lights up.
But it happens that the pressure has dropped, and the lamp does not light up - this is dangerous and the malfunction must be urgently fixed. Why, we will consider further.
Why do I need an oil pressure lamp on the dashboard
The indicator is connected to an electric oil pressure sensor. If it is on, then the pressure is critically low and the engine is operating in oil starvation mode.
A lamp in the form of an oiler can inform the driver:
- About problems with the oil filter. After the engine is stopped, some small amount of oil should remain in the filter, which is necessary for the next starts of the internal combustion engine. If suddenly the filter is dry, the indicator will light up;
- About oil pump problems. When the pump does not create the required pressure, the corresponding lamp is on;
- About blockage of the screen in the pump - it protects the system from debris. If poor-quality lubricant is poured into the motor, the mesh will quickly clog;
- On closing the circuit of the indicator operation circuit.
Why does the lamp not light up when the ignition is turned on?
If the alarm indicator does not work, then this is a consequence of a short circuit in the wiring. In this case, this can be easily checked - just remove the terminal.
Then it is closed to ground - the indicator should be on. In this case, most likely, the sensor is not working.
If the lamp does not light, then you should look for damage in the wiring, such as worn wire insulation or a break.
How to troubleshoot
Failures associated with the indication on the instrument panel can lead to serious problems and expensive engine repairs in the future, so do not be too lazy to find and eliminate the cause of the failure in a timely manner.
Some drivers drive without a lamp, but not everyone is lucky and not always.
Light bulb replacement
Often, after diagnosing the wiring, it turns out that the malfunction is not related to the contacts, the sensor or the circuit, but to the burnt out lamp.
In this case, it remains only to replace the light bulb, maybe an LED. The element itself is located in the dashboard.
On domestic cars, replacing the lamp is not difficult. The hardest part is removing the dashboard.
On domestic machines, all these operations can be done independently. On modern foreign cars, it is better to entrust the work to specialists or watch a video instruction.
Diagnosis or replacement of the oil pressure sensor
There are two types of sensors - electronic and mechanical.
The electronic one consists of a housing, a membrane, contact elements, a pusher and a lamp in the cabin. When the motor is not running, the membrane inside the housing is straightened.
The pusher is in the normal position, and the contacts are in the closed state. After the car owner starts the engine, the lamp lights up, and in the lubrication system, oil presses on the membrane. The membrane through the pusher leads to opening of the contacts.
The electronic sensor can be diagnosed with a multimeter and a light indicator.
Working with a multimeter comes down to the following steps:
- The multimeter is set to dialing mode;
- One probe connects to the central contact of the sensor, and the second - to the "mass";
- With the help of a pump, pressure is created - approximately 1-1,5 atm .;
- If the multimeter does not beep, then the sensor is working. If it beeps, then the sensor is faulty and needs to be replaced.
The mechanical sensor is arranged differently. It also consists of a body, a membrane with a pusher, a slider and a nichrome winding. The oil acts on the slider. As a result, it rises or falls. Each such movement is recorded and sent to the light indication in the cabin.
You can check the mechanical sensor with a pressure gauge, but you need an electronic device. What need to do:
- On the pressure regulator, you need to find the output that sends a pulse to the emergency oil pressure light;
- Find the contact from which the signal is sent to the pressure indicator;
- Connect the positive and negative power wires, as well as a pulse from the pressure gauge (there are three contacts on the sensor);
- Create a pressure of about 1-2 atm. If the sensor is working properly, then the dial gauge will show this with the movement of the arrow. If the sensor is not working, the arrow will remain stationary.
If, as a result of the check, it turned out that the sensor does not work and needs to be replaced, then it must be unscrewed with the appropriate key, and a new one should be installed in its place.
You must not forget to connect the terminal to the sensor contact. After that, the lamp will burn as intended by the manufacturer.
How to check oil pressure
To make sure that the lubrication system is working properly, you can check the actual state of affairs using a pressure gauge.
The motor is started and warmed up to operating temperatures. Then the ICE is silenced. Next, the standard sensor is removed, and a pressure gauge is installed in its place, perhaps for this you will need an appropriate adapter.
Then the motor is started again and the current values \uXNUMXb\uXNUMXbshould be displayed on the pressure gauge - they are usually compared with the values \uXNUMXb\uXNUMXbfrom the instructions for the car.
Checking the quality of engine oil and oil filter
Problems in the oil system are also related to the quality of the oil. Under heavy loads and low-quality lubricant filled in, the pump simply cannot give out performance.
Motorists have come up with a lot of ways to check the quality of fuel and lubricants. If you drop oil on paper, then after a few hours the edges of the stain should be smooth, and the stain itself should spread over the sheet.
The filter in the oil system is compressed paper. When oil moves through it, the filter element must trap debris. In poor quality filters, the paper tears quickly.
And most importantly, never forget to check the oil with a dipstick. Constant level control will avoid a lot of serious problems.
