transfer case engages but it does not send it to the front wheels on 2000 Mercury Mountaineer

I have checked the fuses and looked at the cyloid a friend said give it a few taps it might be suck. This has been like this for years I would like to fix the problem. Any additional fuses I don't know about or part to check or replacement parts would be helpful Thanks The truck runs great other than that.

Asked by for the 2000 Mercury Mountaineer
You are on the right track, you have to inspect the electrical and mechanical side of the drive system. There is a company that independent auto repair shops get their information from, this same information is available inexpensively for people that work on their own cars.. The information is year make and model specific, covering repair procedures, torque specifications, fluid capacities and specifications, service bulletins, component locations, wiring diagrams ect.... Alldata is very easy to navigate
Thank you for the info,it looks good have a good day.