when i push the button for 4wdhi the lights for 4wdhi and low flash and it stays in 2wd,i had a similar problem with it not shifting out of 4x4hi until i replaced the switch on the dash.and my otc scanner wont communicate in transfer case mode but will for engine data this sound familiar to anyone??

 

acutator/motor really common failure,

check your vac lines first and make sure there isn't any disconnected or dry rotted lines.

 

<3 this has helped me!!!!!!

 

actuator/motor were replaced last summer..how can i tell if ecu is bad or not??

 

the ecu would have nothing to do with your 4wd, that would be your tcm

 

control module for the transfer case??how do you know if its bad?

 

check this out https://blazerforum.com/forum/showth...control+module