Similar to other four-wheel drives, a blinking service 4WD light in a Ram truck indicates that there is something wrong with your 4WD system. What does it mean, and how should you react when this indicator turns on all of a sudden?

In this write-up, we will discuss how to clear service 4WD light in Ram vehicles by citing two specific models.

How To Clear Service 4WD Light In Ram Trucks?

When you see the service 4WD coming on while you are driving, there could be a host of explanations. In some cases, a faulty 4WD system can set off the light. It could be damaged front or rear axles; there could be something wrong with the transfer case, or perhaps, the sensors malfunctioning.

The underlying issue could be something far more innocuous as well, like faulty computers. So, there is no need to panic when the 4WD light sets off. Park the car as soon as you can and take a look. If you can’t get to the root of the issue, you need to consult a mechanic at your earliest convenience.

If you are a Ram driver and have been wondering how to stop the service 4WD light from going off, you have come to the right place. We will discuss this separately for two different Ram models: the 1500 and 3500. Ram 1500 is the most popular Ram model in the country.

In contrast, Ram 3500 caters to a more limited consumer base, but it’s popular in its category.

So, we decided to cover both of these models in this guideline. You would frequently come across posts from Ram 1500 and Ram 3500 users in forums seeking solutions for their 4WD light troubles. We will begin our discussion with 1500, and we will move on to the heavier model later on. Let’s begin.

How To Clear Service 4WD Light Ram 1500

Step 1. Park The Car And Stop The Engine

When you see the service 4WD light, park the vehicle as soon as you can. After you stop the vehicle, turn off the engine but keep the ignition on.

Step 2. Connect A Scanner

As we said before, a number of issues can trigger the service 4WD light. You need to pinpoint the reason that prompted your truck’s internal inspection system to activate the light. So, connect a diagnostic tool to the car via the Diagnostic Link Connector. You should find it right beneath the instrument panel on the driver’s side.

Unless you are driving a vintage Ram 1500 that was made before 1996, you would need an OBD-II-supported diagnostic tool to scan the truck. Not all scanners come OBD-II compatible, particularly the cheaper ones. So, you must make sure that the scanner you are using is capable of reading OBD-II data.

Step 3. Run A Scan

The scanner will access the dashboard computer of your Ram 1500 once it connects to the vehicle. However, the key needs to be left in the ignition for the scanner to be able to retrieve the computer data. The diagnostic tool would need the power to function. Switching off the ignition would cut the current flow to the scanner from the car’s battery.

So, why not do this when the car is running? Can anyone sitting in the driver’s seat scan the vehicle while the driver drives it? That would be quite dangerous. Scanning the truck while the engine is operational can overload it.

In the worst-case scenario, it could catch fire and lead to severe injuries. There’s also a high risk of electrocution.

Not to mention, it would put severe stress on the truck battery. The battery is highly susceptible to draining out when you are driving the car and have a scanner attached for extended periods. Also, the computer might fail to deliver accurate diagnostic information when the engine has been running for a long time.

Some scanners can automatically detect your vehicle details, but some models require you to input them manually.

Type in the model name of your vehicle and year, and the scanner should be ready to pull your vehicle information. Depending on the scanner, you would need to wait seconds or minutes for the scan results to pop up on the screen.

Step 4. Look Up The Codes And Make Repairs Accordingly

The scanner will give you some Diagnostic Trouble Codes. You can look them up on the internet to find out what they mean. After you determine what went wrong, fix the problem. If you get a P0836, for instance, it means that the four-wheel drive (4WD) switch circuit in your Ram 1500 is busted. You might need to change the 4WD switch to remedy the situation.

Step 5. Clear The Code

Reconnect the diagnostic tool and scan the truck after finishing the repair. The codes might reappear, but now you will be able to clear them. Now, start the engine and check whether the service 4WD icon resurfaces on the dashboard or not. If it doesn’t, it would mean that you have successfully dealt with the underlying issue that was triggering the light.

How To Clear Service 4WD Light Ram 1500 Without Fixing The Problem

If you don’t have enough time to fix the problem and want to get back to it at a convenient time later, there is a simple trick that can help the light to go away temporarily. A word of warning, however, you should not attempt this when the service 4WD icon is blinking or turns red. This indicates a serious problem that requires immediate attention.

We recommend doing this only when the service 4WD indicator is yellow. The yellow sign implies that the problem is not an emergency, but you should check it out whenever you can see afterward. In other scenarios, driving without addressing the root cause of the service 4WD warning would be dangerous.

With all that out of the way, let’s find out how you can bypass the service 4WD warning.

Step 1. Stop The Vehicle

Park the vehicle and stop the engine. Take out the ignition key as well. You will not be accessing the onboard computer this time around. In fact, leaving the ignition on would be a risky move for what you are about to do. So, make sure both the engine and the ignition are switched off before you proceed to the next step.

Step 2. Take Off The Knee Bolster And The Dash Bezel

Now, remove the knee bolster and the dash bezel. Pick up a flathead screwdriver to gently pull out the air vent grills that sit on either side of the dash bezel. Undo the screws to remove them completely. Then, use the screwdriver to pry off the trim piece that encloses the instrument cluster. You might need to give this some effort, but don’t pull too hard.

Locate the pair of screws at the base of the knee bolster. Undo them and slowly pry off the bolster. Disconnect all wirings connected to the bolster and slowly bring it out. Undo the remaining screws that secure the dash bezel and then disconnect the wirings. After that, remove the dash bezel.

Step 3. Remove The Switch Assembly

After removing the knee bolster and the dash bezel, you need to take the switch assembly out. Since the dashboard is already bare, you don’t have to do much to remove the switch assembly. You can simply pull it out of the case. Moderate force should be sufficient for the job. Again, pulling too hard might damage the switch assembly.

Step 4. Disconnect The TCCM

Before you get to the Transfer Case Control Module (TCCM), you should turn on the engine and the service 4WD status. If it’s already gone, then no need to unplug the TCCM.

But If the notification is still there, however, switch off the engine and the ignition, and unplug the TCCM. You will see a pair of wires coming out from it. Disconnect them.

Step 5. Disconnect The Negative Terminal Of The Battery

If the service 4WD notification refuses to go away, disconnect the negative battery terminal and leave it like that for about an hour.

Reconnect them afterward and make sure the terminal connections are tight enough. Restart the car, and the service 4WD message should disappear from the dashboard.

How To Clear Service 4WD Light Ram 3500

Ram 3500 is a more heavy-duty truck than the Ram 1500. But you can follow the exact same steps to clear the service 4WD lights in both the Ram 1500 and Ram 3500.

You need to follow the same precautions in both cases. The DTCs are also similar. So, if you can clear the service 4WD light in a Ram 1500, you can easily do so in a Ram 3500.

Final Words

Even if you know how to clear service 4WD light in your Ram truck, you must prioritize solving the underlying issue over a temporary solution. Ignoring the problem would not be wise as it would keep deteriorating the condition of your vehicle behind the scenes.

Also, it would be incredibly risky to regularly drive a truck that continuously sends out service 4WD warnings.

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Mark Williams

Founder and Author at Theautomobily

Mark Williams is the founder and author of Theautomobily located in Tucson, AZ. As a Mechanical Engineer,He has 15 years of experience in the automobile industry. Mark's deep understanding of various types of vehicles such as UTVs, ATVs, cars, Trucks, and lawnmowers which allows him to provide valuable insights and information.