Home » How to reset check engine light on Peterbilt 579 and 389?

How to reset check engine light on Peterbilt 579 and 389?

How to reset check engine light on Peterbilt 579 and 389?The check engine light is a distributive signal from the car’s main engine and internal computer that something is not going well in the car’s functions. One of the common reasons for any check engine light is probably a defective gas cap. The gas cap has been screwed in a tight manner, and it is one of the most devastating causes of the CEL in operation. There are diversified types of warning lights, from tire pressure warning lights to low oil pressure lights to the interior CEL of the parts. Check engine lights most of the time come in orange or yellow color, and it solely depends on the specific manufacturer of that vehicle.

If the light is in operation mode, then it denotes a more spurious problem, as a misfire can quickly overheat the catalytic converter inside the primary engine. These emissions from the vehicle operate at exorbitant temperatures to reduce emissions, but it can pose a fire hazard if something nasty is ongoing inside the vehicle. 

Short disclaimer: Peterbilt 579 and Peterbilt 389

Peterbilt is a renowned brand for manufacturing the most destructive and robust truck of all time. The Peterbilt 579 is one of their smooth creations that has set the market in a blaze, and the hype has gotten much more intense as they launch their signature item Peterbilt 579 and 389. Let us have a short overview of these two rigorous trucks, 

Peterbilt 579

The Peterbilt 579 is a tremendous piece of the truck with an intense collaboration of ergonomic and mechanical arrangements. This truck is validated to minimize the purchasing and repair costs. It has an ergonomic dimension and designation of a fantastic speculative part. It has a durable and high-quality matte finish. The mileage and speed are also breathtakingly impressive, and you must check this item if you are committed to having a rigorous truck. 

Peterbilt 389

Another colossal edition from the Peterbilt is coming to amaze you in a stunning way. The Peterbilt 389 is a truck that you can rely on for transporting a heavy-duty purpose. This truck has been incorporated with a staggering PACCAR-MX 13 engine that can withstand a heavy toll. This transport is a real spunk. It has a digital Bluetooth display, a spacious cab, and a super-sleeving sleeper. Every Peterbilt truck is equipped with rigorous and passive safety attributes to protect the driver and those around the vehicle. So it is an automatic pick if you need a truck.  

Why is resetting the check engine light crucial? 

The CEL is a standard method of indicating something unusual going on inside the vehicle. It is a must-have indicator in any vehicle that is out of any context. You must have known that all vehicles have check engine lights to give rudimentary alerts to the driver that there is something fishy in the vehicle’s system. The CEL indicates the engine performance in a broad and wild manner, so it is very crucial to reset the CEL. Some of the vicious reasons for resetting the CEL in the Peterbilt 579 and Peterbilt 389 are given in a nutshell, Why is resetting the check engine light crucial

  • The oxygen (O2) sensor in the Peterbilt 579 and 389 may sometimes misbehave, which will be proven unethical in the system, so always reset the CEL. 
  • Clogged catalytic converters and malfunctioning Mass Air Flow sensors are very much common in Peterbilt 579 and Peterbilt 389 trucks. That is one of the reasons for a decisive CEL, so reset that.
  • Expired spark plugs produce unwanted CEL, so it is prudent to reset that in the shortest possible time. Always reset the radio jacks, seat memory, and the Check lights engine.

How to smartly reset check engine light on Peterbilt 579 and 389

Peterbilt 579 and Peterbilt 389 are two of the most dominant forces in the arena of trucks and heavy-duty vehicles. So many methods are available in the system, making it possible to reset CEL. Let us see those methods in a hierarchical order,


At the very first step, you need to push the ignition key, put on safety gear, and then put on the glasses and gloves for an extra layer of safety. You must remember that no dirt or foreign materials are under the hood.

Then locate the negative terminal that has been attached to the black portion. It has a black cap and a negative vestige on top of the main attributes. After that, you must remove the cable, then loosen the nut with the help of a wrench before pulling the negative portion out of the battery. 

You need to reconnect and realign the negative cable in the next step. This process is only applicable if your light is blinking continuously.

If this process doesn’t work in a progressive manner, then you need to seek an alternative. In Peterbilt 579 and Peterbilt 389, one thing is common: the positive and negative terminals sometimes misbehave, and then there are some measures to be taken that are reconnecting and distributing the channels and the wires in the opposite direction.


Another method is to apply an OBD2 scanner to reset the CEL in the Peterbilt 579 and 389. For detecting and locating your car’s OBD port, it is usually situated in the driver’s seat, and sometimes it is located under the truck’s hood. Then plug the ignition key on the fixed spot and then allow the OBD2 device to connect at the port, and then it will start its scanning process. 

In the next step, turn on the scanning process, and you will find the read mode at some point in the scanning procedure. Then normally scroll through the codes efficiently in order to have sole safety. Write down each code or use the live data stream mode in case the codes revert or change later down the road. Now you will have some set of codes, then select clear the codes by using the “delete the codes” option; this means you can reset the check engine light in Peterbilt 579 and 389. 

Hi, I am Henry, the owner of this website. If you are a DIY car enthusiast like me and are looking for an all-purpose OBD2 scanner, you’ve come to the right place. With 5+ years of experience in the automobile industry, I have in-depth knowledge about most of the OBD2 scanners regarding their software versions, firmware, features, updates, and compatibility. I love reviewing these gadgets after using and testing them personally. As a result, I always try to provide my honest opinion on the overall product quality.


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