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Q: Cannot switch to four-wheel drive

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The car has a 6-cylinder engine and the four-wheel drive. The problem is that I cannot switch from two to four-wheel drive. According to the manual, this is done by pressing the button while driving at speeds under 60 mph. Also, the car has to be moving constantly and that is how it switches to other modes of driving. I tried doing this and the light activates and starts to blink and keeps blinking when it is supposed to remain on. I don't know how to switch it. Do you have any idea?

Hello. A flashing 4WD light is an indicator that the computer has detected that the 4WD is not engaged. This can commonly be caused by a faulty 4WD vacuum servo or loose vacuum hose. I would check to see that everything is connected properly. The vacuum servo is located on the transfer case and will have a vacuum line going to the engine. If those are not the issue, then it may be possible that the transfer case may be having other, perhaps mechanical, issues. If you need help getting this checked, a certified professional from YourMechanic can come to your location to inspect the shifting problem.

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