I need help troubleshooting and repairing 2003 chevy blazer 4x4 drive

Londonderry NH

Description

My 4x4 is getting stuck shifting from 2wd hi to 4wd hi The electronic indicator is flashing yellow vs solid yellow. It doesn't shift to 4wd low or 4wd auto also. I need someone with specific experience with this. Chevy blazer vechile and this 4 wd setup. The electronic control switch on the dash appears to be operating properly, and the actuator under the battery tray is moving as expected. Please repiy with your name, Tel #, experience, and availability. Thx Rob