That's why the plug under your hood didn't work. The scanner you were using is for OBD II! Get an OBD I scanner or use a paper clip. Use plugs under hood on passenger side. Remember, there are two plugs that you'll have to plug in. A large one and a small one. Once again, forget about the under dash plug. If you don't believe us .... pull out your Hayne's or Chilton's manual & look for yourself ... or do a search online.