Unlike two-wheel drive cars, vehicles equipped with four-wheel drive i.e. (4WD) have a transfer case that takes power from the engine and sends it to the front and rear wheels. Most four-wheel-drive vehicles also have a low and high range depending on the situation. Even though a button or shifter is used to activate a four-wheel drive, automakers include a 4wd light on dashboard to let the driver know what setting is used.
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What Does The 4wd Light On Dashboard Means?
When the 4WD light appears, it is letting you know that there is an issue with the 4WD system and it must be handled promptly.
Another reason why this light may occur is an incomplete shift in gears. This is confusing and damaging to the engine and could result in your 4WD service light flashing continuously.
Some vehicles may only have an indicator for the low range as the high range is the default. Refer to the owner’s manual of your vehicle for specific information on your four-wheel-drive system.
However, newer model vehicles have started using electronics to control the four-wheel drive. Some of these electronically controlled systems have a 4×4 automatic mode. This mode keeps the vehicle in two-wheel drive mode for most of the time until extra traction is necessary. The car’s computer monitors the wheel’s rotational speeds and if it notices any slipping, it will send the power to all four wheels to keep the car moving.
What Are The Causes Of The 4wd Light On The Dashboard?
It’s never a good sign when a warning light illuminates, but it’s not necessarily true that your four-wheel-drive system has failed.
Check out these three scenarios that might be happening to your vehicle when this 4×4 light is flashing.
1. Overheated Transfer Case:-
If you find yourself stuck to the point where your wheels can’t move, continuing to hit the gas can generate significant heat inside your vehicle’s transfer case. The transfer case is what splits the power between the front and rear axles. If it overheats, it may no longer be able to operate according to spec, causing the 4WD light to flash. Sometimes, the flashing light signifies that the system itself has been deactivated until it can cool down.
2. Sensor Failure:-
Your vehicle’s four-wheel-drive system relies on information from a network of sensors and switches. That tells it everything from throttle position to wheel speed to transmission speed to physical component location. If one or more of these sensors or switches isn’t working properly. And also not providing any data or transmitting a reading that is well outside the norm it could cause the 4WD light to flash on your dash.
3. Normally Working System:-
A lot of the time, a flashing 4wd light on dashboard is no reason to be alarmed. Because it simply means that the system is working as designed. On vehicles where four-wheel drive is only activated on-demand that is to say when traction conditions require it this light shows up to tell you that it’s been activated. In a way, it’s similar to the stability control or traction control lights on your dash, which also come on the dashboard when their respective systems are called into action.
4. The Rear Diff Locker:-
This is another culprit that could result in a flashing 4WD signal on the dashboard. This signal might be red in color instead of orange. This happens when you are in 4WD 4Lo (Low range) mode and you want to engage the rear diff locker. The rear diff locker also uses a type of electric actuator to engage the locker inside the differential. The rear locker is used under challenging off-road situations where you require maximum traction on as many wheels as possible.
5. Faulty Signals:-
A fourth and final reason why your 4-wheel drive light is flashing and 4WD fails to engage could be due to a faulty signal. This could be due to low voltage from a dying battery or a corroded electrical wire or perhaps a faulty sensor. Could also be a faulty switch on the dash or a blown fuse. These are possible culprits of a modern 4 wheel drive system:
1. Failed Actuator
2. Dirty actuator connector
3. Low Battery voltage
4. Corroded electrical wire
5. Faulty sensor
6. Faulty dashboard switch
7. Blown fuse
What Is The Working Of A Four-Wheel Drive System?
A four-wheel-drive system can be understood as a combination of the FWD system and the RWD system acting in tandem, which enables the engine to connect to and send power to all four wheels. A four-wheel-drive system can either be active at all times or switch between 2WD and 4WD, as required.
A 4WD system distributes power to all 4 wheels of the car through the differentials. In high-traction driving, for example, on the road, it is usually unnecessary to engage 4WD and power is only directed to the rear wheels. Upon encountering a low-traction situation, such as ice or sludge, the differentials can be adjusted to send maximum power to the wheels that have the maximum traction. This enables the vehicle to overcome slippery terrain without losing control.
Pros And Cons Of A Four-Wheel Drive System?
Pros:-
1. Improved traction, as power gets sent to all four wheels.
2. A vehicle can overcome arduous terrain easily, as there is greater control over the amount of power that gets sent to each wheel.
Cons:-
1. Increased fuel consumption.
2. Use of 4WD in high-traction situations can be incredibly stressful to mechanical parts, especially during turns.
3. Makes the entire drivetrain bulky and complex to service.
Is It Safe To Drive With The Four-Wheel Drive Indicator Lights On?
You should never engage four-wheel drive on dry pavement. The four-wheel-drive requires some slippage to occur between the front and rear wheels which is why it’s perfect for gravel, snow, and sand. On dry pavement, the grip prevents any slipping from happening, and enabling four-wheel drive will overstress the drivetrain. Vehicles equipped with automatic four-wheel drive switch between the modes on demand so you don’t need to worry about switching it yourself. However, using the four-wheel drive in slippery situations makes a huge difference to the vehicle’s driveability.
What To Do If The Four-Wheel Drive Indicator Light Comes On?
When any notification appears on your car’s dash, it can cause a fair amount of stress, especially if you don’t know how serious the alert may be. When the light starts to flash, this means there is a problem with your vehicle’s 4WD system. It can either have a mechanical or electrical issue depending on what type of warning you are receiving from the low-light circuit board.
Step 1: Inspect Your Service Forward Light
Initially, you have to check whether the 4wd light on the dashboard is visible or not. Now how to read service 4wd code? Just look at your dashboard, it will show you a light that blinks to say ‘Service 4wd’.
Step 2: Remove The Dash Panel And Knee Bolster
Upon seeing this light, you have to take off your dash panel and knee bolster for closer inspection. You can do this easily as the bezel will just snap out, and for the bolster, you have to undo two screws at the bottom for it to snap out at the top.
Step 3: Pull-On Switch Assembly
Afterward, pull strongly onto the assembly of switches. Make sure you are pulling on all sides evenly so that it does not break.
Step 4: Unplugging Transfer Case Control Module
Then behind this assembly of switches, you will find the smalltransfer case control module. Next, you have to unplug the two wires that go into this small grey box.
Step 5: Undo The Negative Cable On The Battery
Finally, start up your vehicle and check whether the service 4wd light is still there. If it is, undo the negative cable on your battery and take a nap or have something to eat while it rests for an hour or so and that should do the trick.
Step 6:- Shifting Gears Properly
The 4wd light on dashboard may occur because of an incomplete shift in gears. In order to avoid this, make sure to shift completely before taking off for a drive. If you believe you have shifted into gear properly but the light is still on, get to a professional mechanic as soon as possible.
Step 7:- Determine Mecahnical Problem
Like a regular computer, a vehicle computer may go through programming faults that trigger an alert. Pay attention to the timing of your flashes in order to determine if it is a computer or mechanical problem. Many times, computer-related issues may trigger other hidden issues within the car. Because of this, it is imperative to take these issues seriously.
Therefore, if you have followed all these steps and if you still witness the 4wd light it’s better to seek the help of a professional as soon as possible.
How Much Does It Cost To Service 4 Wheel Drive Light?
This mainly depends on your vehicle. The model and type of yourfour-wheeler will determine the cost of the process. Alongside the process, a certain amount of cost for the labor will be between 400-800$ provided to carry out the repair.
Conclusion:-
We hope the above-mentioned information about the 4wd light on dashboard will be helpful to all the readers. If anybody’s doubts persist feel free to comment in the comment section below. We’ll try to solve your doubts as soon as possible.