Freightliner Shuts Off While Driving? Surprising Reasons Why it Happens

When your freightliner shuts off while driving, it can be quite a concerning ordeal to face.

But did you know that you are probably not the only one experiencing this problem.

In fact, the DTNA reports a recall that affected about 122,000 Freightliner, as well as Western Star units that are equipped with battery cables made of aluminum.

On these vehicles, there is a battery cable terminal located at the frame, and this may break and cause electrical power loss. Thus, the engine ends up shutting down even without warning.

This is why the vehicle may simply shut down, and this can be quite hazardous and at a high risk of a crash. This report started in the early parts of 2021, and investigations were made according to this matter.

Furthermore, there were tests that revealed incompatible galvanic materials such as brass and aluminum used, which were not sealed appropriately. Hence, debris intrusion occurs, which can lead to a progressive damage to the vehicle’s weld joint area.

Among the makes and models that were affected by the recall include the Freightliner Cascadia P4 2019 to 2022 models, as well as a few Western Star vehicles.

This is why an inspection to the aluminum battery cables were made to check for corrosion and damage. Then, these need to be replaced or repaired with copper cables.

Find out why your freightliner shuts off while driving and what you can do about it. Let’s dive right into it.

freightliner shuts off while driving

Why Your Freightliner Shuts Off While Driving

The very first thing you need to check when your freightliner shuts off as you drive is the battery. Make sure the charging system and the batteries are doing good. Test them using a digital battery tester, and this should be able to confirm any potential issue with internal problems or bad cells. Conduct a load test and the batteries should be able to pass to make sure there is no issue.

Then, inspect the cables in the connections between the starter assembly and the batteries. They should be clean and have no loose connections at all.

Next, keep the ignition switch on, and test for power using a voltage tester. Check each side of the fuse and replace a fuse that only has one side with power. This will also let you know if you have lost power through a specific circuit.

You can also check the SAM module and check for any error codes. The same with your ECM history, which you also need to check in case some fault codes are logged and are relevant to the symptoms you are experiencing.

Another thing to take note of when it comes to the freightliner shutting off while driving is that it is possibly shutting down from the reading or the sensor. If it started all of a sudden, then it is an electrical issue. It can also be due to debris getting caught on these components.

But if this is not the case at all, you will have to probe your ignition circuit to your ECM, then inspect to check if there is a voltage loss at all. The most important thing is that you obtain a readout from your scanner, which can easily be identified to save you lots of trouble and time in looking at the wrong thing.

Further Things To Take Note Of

further things to take note of

There are many reasons why your vehicle may just shut off while you drive. It may be that the crankshaft position sensors are faulty, and this is why it is causing your vehicle to completely stop.

Alternatively, you need to check your fuel pump. This component can become faulty when there is no sufficient fuel given to the engine, causing the motor to quickly shut off.

But if this is the reason why your freightliner shuts off while driving, you will need to buy a fuel pump or fix it. The fuel filter can also get clogged, which prevents the pump from providing fuel to your vehicle.

The next most obvious reason why your freightliner just shuts off as you drive is that you are out of fuel. Perhaps your fuel gauge is faulty and is not giving you a correct reading. Thus, you are not fully aware of how much fuel is in your vehicle at all.

So, you may want to test your fuel gauge by filling a gallon of fuel. Observe where the sensor starts the reading – and if it is in the wrong position, then there is your culprit that needs to be fixed.

A problem with your alternator can also impact the electrical system in your vehicle. So, if your freightliner shuts off while driving, it may be due to a bad alternator. This cuts off the power supply that is key to your car components. Thus, the engine just loses power abruptly while at the same time turning off any lights in the dashboard.

But if there is still light and the starter motor still works, then it is not an alternator issue but something else. You need to have your mechanic check this out immediately.

It is also important to note that a broken ignition switch can lead to an immediate shut down of your vehicle. Your freightliner may simply shut off without any warning, and even if you turn the ignition on, nothing happens. Check if the ignition lights are still lit up. If they are not, then your ignition switch is the issue.

And lastly, there are sensors in your vehicle that allows you to check the status of your engine. If the sensors are acting up, then they are not giving you a clear idea on what is actually happening inside the vehicle. Thus, it can simply shut off, which is why you need to take your vehicle to a mechanic to address the problem appropriately.

Read More: How Often Do You Change Oil In A Diesel Truck? Key Facts You Should Know


When your freightliner shuts off while driving, there are numerous reasons behind this issue that needs to be addressed. Find out which one is causing the problem and make sure to seek the help of an expert who can give you a definitive diagnosis and solution once and for all.

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