I have an 01 Chevy blazer with 140,000 miles on it. For the past couple of winters I haven't been able to use my four wheel drive. When you press the auto 4x4 or the 4 hi button the light flashes for awhile then goes back to the 2 hi. It doesn't sound like its doing anything while the light flashes. Recently the service four wheel drive light came on and now all the lights are off on the buttons to select four wheel drive. Even the 2hi light it out. Does anyone have any idea where I could start to get this thing fixed? Thanks in advance!!!!

 

This will get you started.
https://blazerforum.com/forum/tech-a...ill-help-7180/