4x4 doesn't engage

I bought my son a 92 Ranger 4x4 a couple months ago nice truck but the 4x4 doesn't engage (Push button on the dash) . Does anyone know a easy way to troubleshoot this?
Tom O

Since you posted, have you had any luck solving? I have similar problem with 95 4x4 Ranger.

Do you get a light when you push 4x4? Or do you get a grinding sound when trying to engage. If it grinds, then you probably got bad automatic locking hubs, in which you'd just have to replace them with manuals. If absolutely nothing, could be electrical, dealing with the transfer case motor, or the 4x4 switch itself.

Behind the drivers seat(behind the jump seat in the ext. cab)is the 4x4 module.If you have access to a Ford manual,You can confirm whether or not the problem is in the electronics. If not ,you probably have a shift motor that isn't moving the lever far enough,or not at all.

i have a 95 4.0l 5 speed with the electric 4X4, how hard would it be to switch the t-case over to manual shift?

I just replaced the transfer case on my 99 ford ranger. the locking hubs will not stay engaged. replacing the transfer case did not help. Any suggestions? Does anyone know what a chipset is?