4x4 question

my 2001 blazer the 4x4 light flash when i try to switch what could that be and how do i fix it also if i want to change my lower ball joint do i have to remove the drive shaft or can i just take out the 4 little bolts and change it that way with out removing the drive shaft pls help thanks

The lights flashing is the trouble code. It flashes a 2 digit code, what is the code?

Lower ball joints are quite labor intensive. Look in the Blazer Forum, in the "How-To" catagory there are several threads that cover it quite well.

thanks a million i will look for that code and get back to you