2000 blazer stuck between auto 4 wheel and 4 lo. wont go back into 2 wheel or shift into 4 hi. just goes between auto 4wheel and 4lo

Switch may be bad. Change switch should fix it.

there is a electrical actuator on the transfere case that controls when you put in 4 wheel hi or 4 wheel lo and 2 wheel

full size blazer? if so do you know if you have auto locking hubs on front or manual? the manual will have a dial to turn to lock or free. to shift into 4 high this can be done by just moving the shifter into 4hi at slow speeds. to shift into 4lo need to be in nuetral with vehicle stopped or rolling just a little bit like 1-2mph shift into 4 lo and shift back into drive same when shifting back into 2hi from low range.

the vacuum lines run to the hubs behind the brake rotors on the front wheels

your high low range shift solenoid is out!! change it!

i am not sure maybe a sensor give these guys a call they sell only GM-parts its Schram auto & truck parts 1-800-292-1032 and they website is www.schram.com wish you the best of luck Michigan Man.

Change shift solenoid

pull atc 25 amp fuse in underhood fuse center and 10 amp 4wd fuse inside cars fuse box,your problem is in control box behind kick panel on pass. side ,corrosion build up,

Reset the computer by disconnecting the battery. This should solve this. nutetral is for the four lo only to engage.

Mike

A good ground is very imporant on these vehicles