Oil Light Comes on but Oil Is Full: Causes and Solutions

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Oil light comes on but oil is full can be a confusing issue to grasp. In the automotive world, few dilemmas can be as perplexing as an oil light despite having adequate oil.

Oil Light Comes on But Oil Is Full

That said, as a responsible vehicle owner, you have to get to the bottom of the issue. Fortunately, in this post, you will learn the various causes and solutions to triggers of oil light even when your car has enough oil.

What’s the Trigger of Oil Light When Oil Is Adequate?

The trigger of the oil light when oil is adequate is a faulty oil pressure sensor. Even though the oil pressure sensor monitors the oil pressure, when it is faulty it can trigger the oil warning light. This can result from erroneous reading that indicates low oil pressure.

When this happens, you will see an oil light come on the dashboard. The oil pressure sensor triggers the oil pressure light when the oil pressure drops a certain threshold. However, a malfunctioning oil pressure sensor can generate erroneous signals that result in unwarranted activation of the oil light.

Wear and tear over time can make the oil pressure sensor faulty. Also, electrical issues like faulty wiring can disrupt the sensor’s ability to send accurate signals. As a result, it can trigger the dashboard light in question. Therefore, this could explain – my oil light keeps coming on and off while driving.

If you are wondering – is it too late when oil light comes on?

The answer is no. That said, this is a warning sign that you should not ignore. Rather, you should be proactive to establish the trigger of this light. While at it, make sure you avoid driving with oil light on.

Faulty Wiring Can Trigger False Oil Pressure Warnings

Another reason your car can trigger the oil light is faulty wiring. The wiring from the oil sensor sends signals to the onboard computer. When the computer detects an issue with the oil, it triggers the oil light in your dashboard to warn you of the issue. However, when the wiring becomes faulty, it can interfere with the flow of information to the onboard computer.

As a result, faulty wiring can cause the sensor to send inappropriate signals or even interfere with the signals. This can wrongly trigger the oil warning light even when your car has enough oil. The most common causes of faulty wiring are cable exposure to heat or moisture.

In addition, the wiring between the oil sensor and the onboard computer can corrode or become loose. When it happens, it can interfere with the transmission of signals. This in return can trigger the oil warning light. Therefore, if your car’s oil light comes on and off, then you may be experiencing faulty wiring. That said, it is a common concern when the oil light comes on without traces of an oil leak or oil leaks.

Broken Oil Pressure Gauge Can Trigger False Oil Light

If you have a broken oil pressure gauge in your car, it can trigger the oil light. The connection between your car’s oil pressure gauge and the onboard computer makes measuring the oil pressure possible. However, if the gauge is faulty, it can show incorrect readings or fail to register any pressure.

Trigger of Oil Light When Oil Is Adequate

As a result, it can trigger the oil light even when the engine oil level is within the recommended range and the pressure is normal.

There are various reasons why the oil pressure gauge may malfunction or break. For instance, over time the internal components such as electrical or mechanical parts may wear out. This may result in an inaccurate reading. Also, wiring issues or physical damage can make the gauge fail resulting in erroneous oil pressure readings.

Worn Oil Pump Can Trigger False Oil Light Activation

If your vehicle is illuminating the oil light despite having enough oil, the culprit could be a faulty oil pump. The oil pump maintains the circulation of oil throughout the engine. It generates the pressure necessary to make sure oil reaches the vital components of the engine. If the oil light comes on at idle but goes off when driving a worn oil pump could be to blame.

When you have a faulty oil pump, it is unable to maintain adequate pressure which will trigger the oil light. This happens with time as the internal components of the oil pump wear out. They can wear out because of high mileage, contaminants in the oil, or insufficient lubrication.

As the pump wears, the ability to create enough pressure decreases which decreases oil flow in the engine. When the oil pressure sensor detects a decrease in oil pressure, it will trigger the oil light. Keep in mind that even when you have enough oil, the worn pump is unable to generate adequate pressure to distribute it. The light comes on to signal a potential issue.

Using Too Thick or Too Thin Oil Causes Oil Warning

If you are using too thick or too thin oil, it can trigger the oil light when the oil level is okay. The viscosity or thickness of oil plays an important role in providing lubrication and dissipating heat. However, when you use too thick or too viscous engine oil for the engine, it will interfere with oil flow resulting in a drop in oil pressure.

Using Too Thick or Too Thin Car Oil

The pressure drop will trigger the oil sensor which in return activates the oil light on your dashboard. If the oil is too thick, it resists flow, especially in cold starts. On the other hand, using too thin engine oil can activate the oil pressure warning light.

Although the oil flows easily it provides inadequate lubrication resulting in increased heat and friction that leads to a drop in oil pressure. This subsequently activates the oil light. If the oil pressure light comes on when engine is hot, you are likely using the wrong motor oil. This can even trigger the check engine light.

A Clogged Oil Filter Can Activate the Oil Warning Light

A clogged oil filter is another culprit that could be behind the oil light coming on even when the oil is full. The oil filter removes debris and contaminants from the engine oil. However, if it gets clogged or blocked, it will restrict the flow of oil through it.

The clogged oil filter apart from interfering with the flow of the oil, also decreases oil pressure. As a result, the pressure sensor will detect the drop triggering the oil indicator light. Over time, the clogged oil passages such as the pickup tube and oil filter can arise from the buildup of sludge, debris, or contaminants. It is a sign that the oil filter has reached its capacity.

Which Is the Best Solution to Oil Light With Enough Oil?

The best solution to oil light with enough oil in your car is to replace the faulty oil pressure sensor. When you replace the faulty sensor, you restore accurate oil pressure readings. This is going to ensure that the light comes on when there is a genuine pressure drop.

To replace the faulty sensor, you will need a professional mechanic to diagnose the sensor. After establishing the sensor is the cause of the issue, you will have to replace it with a functioning one.

Once you are done with the replacement, the new oil pressure sensor will accurately measure the oil pressure. As a result, the light will remain off until there is a legitimate decrease in oil pressure to activate it. That is how to reset low oil pressure light effectively.

Repair or Replace Faulty Oil Pump: Solve Oil Light Alarms

Another effective solution entails replacing or repairing a damaged oil pump. This solution requires expertise to establish if the oil pump is repairable or it needs replacement. If you have the skill and the pump is repairable, you can replace worn components to restore the oil pump’s ability.

If the pump is irreparable, you will have to replace it. This requires removing the faulty one and installing a new pump. While at it, make sure the new pump meets your vehicle manufacturer’s specifications. The replacement will provide optimal oil pressure.

Therefore, repairing or replacing the oil pump restores the proper oil pressure which eliminates the oil warning light. In the future, you can avoid this unnerving experience by doing regular maintenance.

Fixing Wiring Problems Resolves Illuminated Oil Light

You can also effectively solve this issue by fixing wiring issues. When you do this, you restore the integrity of the electrical circuit that sends oil pressure information. However, this requires inspecting the wiring system for visible damage, corrosion, or loose connection.

Fixing Oil Light With Enough Oil

If you find frayed or damaged wires, you can repair or replace them. You can tighten loose connections for a secure and reliable connection. As well, you can fix any electrical faults in the circuit. Once you fix the wiring issues between the oil pressure sensor and the dashboard, you will restore proper communication. As such, the warning light will only turn on when there is a genuine drop in oil pressure.

Using the Right Oil Quality To Correct Oil Light Activation

Another way of effectively solving this issue is using the right quality of engine oil. To do this, you need to check the recommended oil type and viscosity for your vehicle. This is what to do when oil light comes on. You will find relevant information in the owner’s manual.

Using high-quality oil that meets the manufacturer’s guidelines offers the necessary lubrication and consistent oil pressure. This way, the oil light will only turn on when there is a legitimate reason like a drop in oil pressure.

Also, make sure you perform regular oil change as per the manufacturer’s recommended intervals. With regular oil changes, you ensure the oil remains clean and capable of maintaining oil pressure.

Replacing Dirty Oil Filter To Avoid Activation of Oil Light

Another effective solution entails replacing a dirty oil filter. When you replace an old dirty fuel filter, you restore the flow of oil and maintain the necessary oil pressure. Replacing the oil filter is part of the routine maintenance for any vehicle.

When you regularly replace a dirty oil filter, you allow for optimal oil pressure. The regular changes of both oil and filter help avoid the likelihood of a clogged filter. This way, the warning light will only come on when there is a genuine concern that needs your attention.

Oil Light Comes on But Oil Is Full Details


In this post, you learned the underlying trigger of oil light even when your car has enough oil and how to solve it.

Here are the key takeaways from this post:

  • The major causes of the oil light coming on when the oil is full include a faulty oil pressure sensor, wiring issues, or a broken oil pressure gauge.
  • Solutions to the issue include replacing faulty oil pressure sensor, repairing wiring issues, or using the right quality of oil.
  • Also, you can solve the issue by regularly changing the oil filter.
  • To diagnose and solve the cause of this issue, you will need a qualified mechanic.

With this understanding, you can now check the various triggers of this warning light and solve the issue effectively.

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