Ok my mom has a 94 fj80 with the front and rear diff locks. the other day i was driving it through a ditch and got one of the front wheels in the air, the truck was in 4-low and i had the diff switch to both front and rear. i could have easily made it across but it concerned me that thw front wheel once off the ground started spinning while the other front tire was doing nothing, whne i truned the diff lock swith on none of the indicator lights on the dash came on. could my diff locks be broken or for some reason not working? thanks