I have never had this problem with my LUV, but i did have this same problem with my parent's '87 GMC Suburban, with the Sub. the problem was with the the ignition key (the thing you put the key into to have acc. and to start the truck) it was worn out and wasen't disengaging when you turned the key to "off". I also had a simuler thing happen with my '88 Trooper (Isuzu, same ppl that made the LUV) same thing the key slot thing wasen't disengaging when i turned the key to "off"
First thing I would do would be to check the key and ignition and make sure they are working right , it may be some thing as simple as a lose wire from the ignition so be sure to check the wires. I hope this helps you out some
