i have a 1996 chev. s10 blazer 4 wheel drive.it is electronic. push button select. when i select 4 low or 4 high it engages but the front wheels do not move.help. thanks

 

This is a very common and well covered problem. Search for "actuator". You likely have a problem with either the vacuum supply to the front axle actuator (switch in t-case or vacuum line itself), a faulty actuator, and/or a hard part problem between the actuator and the collar inside the front axle (froze up cable, something broken in the front axle which is the worst case scenario).

 

And its no fun to get too, its under the battery tray. So have to remove the battery andbattery tray to get to it. So have to use jumper cables or a jump pack to supply power to the truck so you can look at the vaccum actuator while you have a buddy hit the button to see if it works, trouble shot it, replace it.