Help 4x4 Don't Work !!!!!!!!!!!!!!!!!!!!!!!

[orviszj]

I HAVE A 1992 LEGACY AWD ONLY THE FRONT WHEELS DRIVE IT A 2.2 NON TURBO AUTOMACTIC THE FWD LIGHT IS NOT ON NO FUSE IN HELP THE REAR WHEELS DO NOTHING BUT GO ALONG FOR THE RIDE

electronic center diff IS THERE ANYWAY TO ENGAGE IT I DO NOT KNOW IF ITS BEEN TOWED JUST BOUGHT IT THEN FOUND OUT THE 4X4 DID NOT WORK [iN MUD] SOMEONE TOLD ME IT COULD BE A SELIOD COULD BE BAD [COULD IT] IF THE electronic center diff IS BAD IS THAT ON THE BACK OF TRANSMISSION??