4WD Overheated Temporarily Unavailable: Causes & Fixes

When you notice a 4WD overheated temporarily unavailable message on your vehicle, it shows the 4WD internal components are overheated. Sometimes, it comes with a burning smell, and when the 4WD is activated, it switches back to 2WD.

The heat from the engine and transmission could contribute to the issues with the 4WD. Problems with the cooling system in the vehicle could also cause it. When the cooling system is damaged, the engine and the transmission system will overheat.

What is 4WD Overheated Temporarily Unavailable?

A 4WD overheated temporarily unavailable is a warning message that comes up when the 4WD system is experiencing overheating. A failing cooling system or low transmission fluid mainly causes it. 

When the 4WD is engaged, the engine will send power to the transmission. The transmission splits the power between the front and rear wheel axles. When this happens, torque is transferred to all the wheels. 

The major parts of the 4WD system are the two differentials and the transfer case. When the 4WD feature is activated, the differential connected to the engine transmits power to the axle, enabling wheels to turn at different rates. 

On the other hand, the transfer case transmits power from the transmission to the front and rear axles. It makes use of a chain-driven arrangement. The transfer case links the differentials with the help of the driveshaft, which then transmits power to the wheel.   

In addition, overheating in the engine or the transmission system will damage the components of 4WD. The “4WD overheated temporarily unavailable” warning message will come up when this happens. 

What are the causes of 4WD Overheated Temporarily Unavailable?

The major cause of a “4WD overheated temporarily unavailable” is a failing cooling system. The cooling system ensures that all the components of the 4WD system remain within the working temperature. 

Below are some of the causes of “4WD overheated temporarily unavailable.”

1. Low or leaking coolants 

The coolant is responsible for cooling the engine; however, it does not stop there; it also cools the transmission system. 

When the engine reaches a particular temperature, the coolant is released and circulated through the engine with the help of the water pump. 

The coolant is cooled by passing the fluid through the metal fins, which lets the heat from the coolant flow to the air outside. Coolant is then circulated through the transmission with the help of the return line before being returned to the radiator. 

When the coolant is low, there is a leak, then the engine and the transmission will not be properly cooled. In this case, overheating is unavoidable. Once there is overeating, the differential and transfer case will be affected.   

2. Failing engine thermostat 

An engine thermostat is a valve part of the vehicle’s cooling system. It monitors the temperature of the engine. Once the engine reaches a certain temperature, the valve opens, and coolant flows. 

The engine will overheat when the thermostat is damaged because it lacks coolants flowing through its blocks. The 4WD components, like the bearing and transfer case, will also overheat when the engine overheats. It will cause the warning message “4WD overheated temporarily unavailable” to come up. 

3. Low or leaking engine oil

The engine oil also plays a crucial role in controlling the engine’s temperature. When the engine oil is low or leaking, friction will increase in the engine’s moving parts.

When this happens, heat accumulates in the engine until it overheats. The transmission will also be affected if it is not managed fast enough. 

4. Low or leaking transmission fluid

A low transmission fluid will affect the transmission in general. Since the differential and transfer cases are linked to the transmission, they may share the same fluid with the transmission system. 

In addition, when the transmission is low, the transmission components will struggle to function and will be less lubricated. It will cause friction to increase, causing overheating within the transmission. 

Overheating in the transmission will affect most 4WD components, causing a warning message. Other symptoms will follow, like difficulty in shifting gear. 

5. Failing 4WD parts 

Also, parts of the 4WD system, like the differential, transfer case, driveshaft, and drive axles, can get damaged and trigger a warning message. In some cases, when these parts lack proper lubrication, they can generate enough heat to trigger warnings in the vehicle. 

How to Fix 4WD Overheated Temporarily Unavailable

There are many factors that could cause a 4WD to overheat and become temporarily unavailable. A proper diagnosis is recommended before a fix can be done. 

Below are some ways to fix a “4WD overheated temporarily unavailable” warning message.

1. Check and fix coolant leaks 

When faced with a coolant leak, the first step is to check the coolant level. The next step is to find out where the coolant is leaking from. Check the radiator, coolant line, and other parts under the hood. 

Once the leak is found, you must replace the part causing the coolant leak. 

2. Replace faulty engine thermostat

It is easy to tell if the thermostat is bad, as you will notice that the engine becomes too hot even when there is enough coolant in the reservoir. You can also use a diagnostic tool to determine if the thermostat is still functioning. 

Once it is determined that the thermostat is bad, the next step is to replace it. The thermostat is located where the top hose joins the engine. 

3. Fix oil leaks 

Check the oil level of the vehicle; if the oil gets low too fast, then there is a leak somewhere. Look below underneath the car after parking for a while; if oil is on the floor, there is a leak. 

Inspect the oil lines, oil pump, oil pan, and more. Once the part of the vehicle causing the leak is found, have it fixed immediately? We recommend professional help with this kind of fix.  

4. Fix leaking transmission fluid

Transmission leaks can be tricky to fix due to how complicated the transmission system is. Find a professional to help properly locate the leak and fix the cause of the transmission fluid leaks. 

5. Fix internal components o the 4WD 

Most of the time, issues with the 4WD internal component could be due to low fluids or inadequate lubrication. Once you can top off the transmission fluid and properly lubricate some essential parts, the 4WD system will return to normal functioning. 

More complicated issues with the 4WD system should be referred to experts for proper repair. 

Final thoughts 

The component of the 4WD is part of the transmission system and is directly influenced by anything that affects the transmission. Proper transmission and engine maintenance will help avoid issues with the 4WD system. Ensure that the coolant fluid and engine oil do not go low, monitor the transmission fluid and top up when necessary.

  • Edmond Davis

    I'm Edmond Davis, an automotive expert with years of experience in vehicle repair, performance, and safety. I graduated from the University of Michigan with a degree in Automotive Engineering and have worked with major companies like Ford, GM, and Chrysler. I'm a trusted source of information for anyone looking to learn more about cars or improve their driving experience.