A transfer case is an essential system component of a vehicle that allows you to change modes of operation. It is the reason why heavy vehicles do best on challenging terrains. A transfer case has 4WD (four-wheel drive) or AWD (all-wheel drive) capability; thus, switching the modes becomes convenient. Also, it provides superior traction to your vehicle and the option to transmit power. The vehicle’s transmission power to the rear and front wheels leads to a successful ride on off-roads. Nevertheless, you should keep testing the transfer case to know its current condition.
So, how to test the transfer case? Generally, the ‘bench test’ and ‘jack stand test’ are done. Still, we have described three tests you can conduct to know what’s happening with the transfer case.
Transfer Case Control Module (TCCM)
The transfer case control module is the thing that controls the operations in the 4WD (four-wheel drive). From processing to verification, the transfer case control module oversees every step.
To see the transfer case motor, you will have to make some modifications to the steering column. Under the steering, there is a trim panel. Remove it, and you will see the transfer case on the right side of the opening. A driveshaft connects the transfer case motor with the actuator, front, and rear axle. A rear axle is responsible for wheel movement, while a front axle helps smooth steering. An actuator is responsible for converting energy into physical activity or force.
A lousy transfer case motor does not allow you to switch from 4WD (four-wheel drive) to AWD (All-wheel drive), and the rear differential will also face the consequences.
How To Test Transfer Case?
Generally, people carry out three tests to see the condition of the transfer case motor.
Jack Stand Test
You can begin by raising your vehicle and putting it on the jack stands. Ensure that the jeep is stable as the tires are off the ground. Also, do this test on a stable or flat surface. If it is sloppy or uneven, the vehicle may have trouble staying on the jack. So, decide the location carefully and follow the steps carefully.
In the next step, start the vehicle. You should put it in a four-wheel-drive mood and low range (4L). Then, you should come out of the vehicle and observe the wheels and front output yoke. The transfer case shift motor is fine if you see the yoke spinning. If the transfer case fails to move the yoke, be prepared to spend some money to repair the transfer case issue.
You can also test transfer cases with the bench test method. You can conduct it in two ways.
Ohm test is the first bench test you can opt for to know the situation of the transfer case motor. Get the jack, jack stand, and an ohmmeter (test light) ready for this method.
First of all, use the jack stands to raise the vehicle. Next, slide under the car and look at the transfer case motor. It is on the transfer case rear with four bolts holding it and looks similar to a window motor. Then, take the transfer case motor out by removing those bolts and any connector wirings attached.
After that, find the orange and yellow wires because they control the motor. You will see the yellow and orange wire on the actuator. Now it is time to use the ohmmeter. Set it on 200 ohms and put the probes on these two wires. The outcome you will get will be 2.2 to 2.7. If you are getting a high range reading, there is a problem with the shift motor. Recording the reading in the range means that the transfer case motor shift is working fine.
Battery Pack / Portable Jumper Pack test
This is the second bench test method that you can opt for to test the transfer case motor. To start, take a car battery or jumper pack for this. Next, connect the multimeter leads with the jumper pack. Also, connect the probes with orange and yellow wires.
In the next step, you will observe the movements. If the movement of the gear is free and, in both ways, the transfer case motor is okay. If not, then you probably have a faulty motor.
How Do I Know If My Transfer Case Is Bad?
Sometimes, you don’t have the time to conduct any tests. In that case, you should be more observant while driving the vehicle. Following are the signals or symptoms your vehicle exhibit when there is any trouble with the transfer case motor:
Gear Shifting Issues
The bad transfer case motor may be the reason behind the damaged gears (although it may also happen due to damage linkage or low fluid). Observe any other trouble you face while driving to confirm if it is due to a faulty transfer case.
Trouble Staying in 4WD for a Longer Period
A lousy transfer case shift motor also doesn’t allow you to stay in 4WD for a longer time. Other factors may also cause this problem which are issues with the center differential or drive shafts. However, you cannot discard the fault in the transfer case encoder motor.
4WD Stops Working
4WD (four-wheel drive) has trouble engaging and disengaging if the transfer case shift motor is lousy. Faulty shift mechanism, electrical fault, and other things can also disrupt the 4WD working.
Illumination of 4WD Warning light
The 4WD warning light illuminates when there is a transfer case shift motor problem. Take it as a warning message by the control system. Moreover, a vehicle also shows a four-wheel service message to indicate that there is a problem with the transfer case motor.
The Vehicle Will Make Weird Noises
When you start hearing the growling noise (like a grinding noise) from the vehicle, be prepared as the significant damage is around the corner. The transfer case may be the reason. So, when that happens, take the vehicle to the workshop, and replace the case immediately.
Causes of Bad Test Transfer Case Shift Motor
The transfer case may go bad due to many reasons, a few of which are listed below.
Transfer case shift motor gets affected when there is an internal or external transmission fluid leak or transfer case fluid leak. Transmission fluid is different from transfer case fluid, but both can destroy many parts in a vehicle, and the transfer case is also no exception.
Thus, you should deal with the fluid leakage right away as it can also cause different mechanical damages. Also, you should regularly change transfer file fluid for smooth functioning.
Lack Of Maintenance
Lack of maintenance is another reason why the transfer case goes bad. You should look at the manual for a maintenance timeline. The manual will have all the details about when your vehicle needs service and maintenance.
Vehicles should have the transfer case motor in acceptable condition as it is responsible for switching the mode of operations while driving. However, due to fluid leakage and lack of maintenance, the transfer case motor might go bad, leading to different troubles. If the issue is timely detected, then the damage is not significant.
To detect this, you should carry out various tests. You can test the transfer case via two different methods. These are the jack stand test and bench test (ohm test and battery pack/ jump test). In addition to this, you should also be attentive to how your vehicle behaves. If you have trouble shifting gears, staying in 4WD is difficult, alarming light is on, hearing growling noises frequently, or 4WD is not working altogether, then it means that there is an issue with the transfer case. In this situation, take the vehicle to the mechanic immediately and get the problem fixed to enjoy smooth and long rides.