How To Fix 1992 Gmc Sierra K1500 : My 1992 Gmc When Shifting Into 4 Wheel Drive It Feels Like It Does But 4x4 Light Does Not Appear. I Have Checked The Wir My 1992 gmc when shifting into 4 wheel drive it feels like it does but 4x4 light does not appear. I have checked the wires they are good. checked fuse and it was blown so I replaced. I unpluged the switch located on the transfer case and put it into 4x4 and still blow fuse? After changing to new fuse. what could this be