Regen Light Still on After Regen: What Does It Mean?

If you own a diesel-fueled vehicle, you probably heard of the Diesel Particulate Filter (DPF). An indicator known as a regen light turns on when you need to run a regeneration. But sometimes, you might see that the regen light is still on after regen. There are numerous solutions for this.

Soot is the possible reason behind such behavior. You must do a passive forced DPF regen if the light’s steady. If there’s still time on your hand, you must park the vehicle and perform parked DPF regen when the light starts flashing. Without the necessary regeneration, your DPF will get clogged, damaging the engine in the long run. 

Maintaining your vehicle is very important. Running regeneration is one of the most important things. Otherwise, it hampers the engine and leads to temporary damage or oil leaking. Sometimes, it makes the exhaust system useless, and an owner needs to use aftermarket catalytic converters.

Why Regen Light Turns On

When you don’t clear the soot of the DPF, you will see the regen light turned on. Depending on how you operate your car, there is no specific limit on how frequently you should perform the regen process. 

It might occur once every day. Some say they go without any regen process for a week. There is no specific time on how often a regen takes place. Soot is a possible reason behind it.

Soot Explained

Diesel soot is a significant environmental contaminant created when diesel fuel burns at high temperatures, either by pyrolysis or combustion. Soot keeps on clotting together in the filter. 

You need to perform a regeneration to clear the soot from the DPF. When you perform regen, you burn the soot in the filter. 

soot explained

Cleaning soot may seem like a simple process, but it isn’t. The process takes some time to complete. The engine will derate and eventually shut down if you don’t perform a regeneration.

What To Do When Regen Light Turns On

You need to keep your vehicle well-tuned. Otherwise, the car is not going to have a long-lasting life. Running a regeneration keeps the engine fresh. But sometimes you might see that the regen and traction control light are still on after you do a regeneration. 

A situation like this shouldn’t occur. But if this happens, here’s what to do: 

If The Light’s Steady

When you see that the regen light is steady, it means the light’s giving you the first warning. So, it would be best if you had some DPF regeneration. 

But there are several hours left to operate the vehicle. In such a situation, you must perform passive regeneration. 

There are two types of passive regen methods. One is “forced DPF regen,” and the other is “parked DPF regen.” 

But in this case, you need to perform the forced DPF regen. Let’s see a better view:

Forced DPF Regen

You start a forced regeneration with the help of a diagnostic scan to begin the regeneration process. The ECM (engine control module) calculates the soot level. But whatever the calculation is, it’s superseded by forced regen. 

Sometimes, it might be necessary to perform a forced regeneration because the DPF soot load is too high for both passive and active regeneration. Forced DPF regeneration is often called the best regeneration method. 

However, you will need access to a specialist diagnostic tool to do this. This process also costs more than other processes. So before you go for this, make sure you try the other methods. As this is costly, you can keep it as a last resort.

Usually, this procedure takes at least 60 minutes. So, have patience during the process, as it’ll be better for your vehicle in the future.

If The Light’s Flashing

When you notice the lights flashing, it’s your second and most urgent warning. Therefore, you must perform the parked regen. In this stage, there’s also a beeping sound to give you an alarm for immediate regeneration.

Parked DPF Regen

One of the simplest mechanisms is the park DPF regen. Most modern diesel-fueled jeeps have parked DPF regeneration systems built into them. 

The only drawback of this process is that this is not available on all cars, especially the older models. Here’s what you should do: 

First, put your car on neutral and pull your hand brake. Put your vehicle at a halt and turn on the hazard lights if you are on a highway. 

After that, check the engine temperature before you hit the regen button. The temperature must not be higher than 76.6C or 170F.

After completing those tasks, you are now prepared to use the “regen” button. Press the button for two seconds for the regen process to start.

Keep in mind that the regen procedure takes 20 to 60 minutes. Do not press anything at this time. Don’t put your foot on the gas paddle if you see the rpm is not normal. It’s a part of the process so wait with patience.

After you have done the process, the regen light should turn off. After that, you are good to take your vehicle out for a nice ride!

The Last Chance!

If you fail to perform the required regeneration, it’s not good for the engine. As a result, the soot won’t be cleared, and the DPF filter will stay clogged. This will damage your V10 engine and cause you to lose performance. 

On top of that, the repair cost will be higher. Therefore, you must shut your rig down when you see the light on or flashing. You can also ask for roadside assistance if there’s any. 

When the light’s steady, you can also drive a few miles and contact the nearest repair shop. 

Remove The DPF 

You can remove the DPF and clean the filter if the regen still doesn’t work. However, it takes some skills. If you know the deal, you are the man for this job. Otherwise, contact the dealer or renowned repair shop. 

Active Regen

Besides passive regeneration processes, you can do an active regeneration process. When you see the regen light on during your travel, there is no need to panic. 

You can fix this issue by driving your vehicle for around 10 minutes at over 65 kilometers per hour. While you are going, the RPM should be 2500 RPM. If you are driving a manual geared vehicle, stay in 3rd gear. 

Also, make sure you have enough fuel. At least keep  3/4th of the fuel tank filled. After driving for more than 10 minutes, the light should turn off. 

But it would help if you kept driving for another 15 minutes even after the light turned off. Otherwise, you might see the regen light turned back on again.

Final Words

As you are driving your vehicle, it is customary to see the regen light flashing. Sometimes even after you perform a regeneration process, you might still see the regen lights on. Before making a final decision, change the oil type for your jeep or car, as sometimes changing the oil fixes this issue automatically.

Hopefully, the discussion has enough coverage to show you what to do when the regen light is still on after regen. Perform the tasks mentioned above to get a better solution. 

Keep your DPF filter clean by following the discussion above, and your vehicle should run smoothly. If you still face difficulty, consult with your nearby mechanic as soon as possible. Happy driving!

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