Solving the Mystery Behind Freightliner DEF Light Blinking but Tank is Full

The Freightliner DEF light may be blinking due to a faulty sensor or electrical issue rather than the tank actually being empty.

Freightliner Def Light Blinking But Tank Is Full

If your Freightliner DEF tank is full but the DEF light is still blinking, there could be several different causes for the issue. It could be as simple as a wiring issue in either the DEF level sensor or a faulty/malfunctioning DEF pump, as well as more complex issues such as an ECU malfunction. Whatever the cause may be, it is important to diagnose and repair it promptly to avoid any potential legal or financial repercussions. To help you with this, we have outlined some of the most common causes and solutions for this type of situation. By following some of these steps, you can identify if a wiring issue or other mechanical problem is what’s causing your DEF light to remain on even when the tank is full.

What is the Freightliner DEF Light?

The Freightliner DEF light is a warning light that alerts drivers of a malfunction with the diesel exhaust fluid system. Diesel exhaust fluid (DEF) is a mixture of urea and water that helps reduce emissions from diesel engine vehicles. The Freightliner DEF light will come on when there is an issue with the fluid or its delivery system, and should be addressed immediately to ensure proper performance of the vehicle.

Why Is My Freightliner DEF Light Blinking?

The Freightliner DEF light will blink when there is a malfunction in the def system. Common causes for this include a clogged filter, low levels of def, or an incorrect mixture of def and water. If your Freightliner DEF light is blinking, it’s important to have it checked immediately.

What Should I Do If My Tank Is Full But My Freightliner DEF Light Is Still Blinking?

If your tank is full but your Freightliner DEF light is still blinking, then you may have a more serious problem with the system. In this case, you should take your vehicle to a certified mechanic as soon as possible so they can diagnose and repair the issue. They may need to replace parts such as sensors or filters or flush out any contaminants in the system.

Can I Continue Driving With A Blinking Freightliner DEF Light?

It’s not recommended that you continue driving with a blinking Freightliner DEF light as it could cause further damage to your vehicle if not addressed quickly. Driving with this warning could also void any warranties you may have on your vehicle so it’s important to get it fixed right away.

What Is Freightliner DEF Light?

Freightliner DEF light is an indicator light that indicates when the Diesel Exhaust Fluid (DEF) tank is low or empty. The DEF tank is part of the vehicles exhaust system and helps to reduce harmful emissions from diesel engines. The light will come on when the DEF tank needs to be refilled. Its important to refill the DEF tank as soon as possible, as running a diesel engine without it can cause damage to the engine and costly repairs.

What To Do When The Light Is On?

When the Freightliner DEF light turns on, it means that the DEF tank needs to be refilled. To do this, you should first locate the DEF tank, which is usually located near or in front of the fuel filler neck or in front of the radiator on most vehicles. Once you have located it, you should open the cap and check how full it is. If its low or empty, then you will need to purchase some Diesel Exhaust Fluid (DEF) and fill it up.

How Much Does It Cost To Refill The Tank?

The cost of refilling a Freightliner DEF tank varies depending on where you purchase your Diesel Exhaust Fluid from and how much you need to fill your tank up. Generally speaking, a gallon of diesel exhaust fluid will cost between $10-$15 depending on where you buy it from.

Freightliner Def Light Blinking But Tank Is Full: What To Do?

If your Freightliner DEF light is blinking but your tank is full, then there could be a few different things causing this issue. First, make sure that all of your connections are secure and properly sealed and that there are no visible leaks coming from anywhere in your system. If everything looks okay then it may be an issue with your sensors or wiring in which case you should take your vehicle into a certified technician for diagnostic testing and repairs if necessary.

FAQ & Answers

Q: What is a Freightliner DEF light?
A: The Freightliner DEF light is an indicator on the dashboard of a Freightliner truck that indicates when the truck is low on diesel exhaust fluid (DEF). This fluid is used to reduce emissions and must be replenished periodically.

Q: Why is my Freightliner DEF light blinking?
A: The Freightliner DEF light will blink when the tank level of DEF is low or has been depleted. This indicates it needs to be refilled in order for the engine to function properly.

Q: What happens if I don’t refill my DEF tank?
A: If you do not refill your DEF tank, your engine will not be able to run efficiently and you may experience reduced performance as well as increased emissions. In some cases, your engine may even shut down completely until the DEF tank has been refilled.

Q: My DEF tank is full but my Freightliner DEF light is still blinking, what should I do?
A: If your tank is full but your DEF light is still blinking, then it likely means that there is an issue with the system itself. You should check all connections and hoses leading to and from the tank, and make sure they are properly secured and sealed. If this does not fix the problem, you should take your vehicle to a qualified mechanic for further inspection.

Q: How often do I need to refill my Freightliner’s DEF tank?
A: The frequency at which you need to refill your Freightliner’s DEF tank will vary depending on how often you use it and how much diesel exhaust fluid (DEF) has been consumed by its operation. Generally speaking, most trucks need to have their tanks refilled every 5,000 miles or so.

The Freightliner Def light blinking but tank is full indicates that there may be an issue with the diesel exhaust fluid (DEF) system. It could be a problem with the DEF filter, DEF pump, or DEF injector. It is recommended to have the system checked by a qualified technician to determine the exact cause of the issue and ensure proper operation of the DEF system.