Here we go again. The diesel has been starting and running fine and when I got home yesterday I shut it off and no indication of any problem. This morning when I went to start it up I noticed that the glow plug light did not come on. Well when this happens it will not start. This happened a few years ago and I ended up changing the chip in the computer. However this time when I put the paper clip in to read the codes I was receiving a 12 so I assume that there is another problem other than the computer. I tried another FSD and another chip and there was no change. I am now open to any suggestions as to what to try. I have been hunting for the wire diagram of the glow plug and starting requirements and have not found it.