Hello all. I have a 1984 Hitachi Seike Hitech Turn 20 in the shop with a Fanuc 10TF control. It is new to my shop and I am trying to get it up and running again. I have been slowly plugging away at one issue at a time. I had started out over in the General Electronics Discussion forum here as the first problem I encountered was a bad electronic component in the spindle drive. I got a lot of great help there and I can't the people who gave me their help enough.

That last problem I have concerns the Operator Panel LEDs. They will not light, not one of them. We kicked this around a bit over in Electronics and looked into several possibilities of an electronic nature there. But I have not been able to get them to work yet. It may still prove to be electronics related, but I figured I would try here in hopes someone may have seen this one before or have new ideas as to the cause. I know I can run the machine without the LEDs working, but where it is new to me and I am unfamiliar with it, I want to have them all going to lessen the chances of an accident.

I have confirmed that all of the LEDs will light through testing them. I just can't get the control to light them. I confirmed that there is 5V present at the annode of each and that all of the cables/wires are good to the board located directly behind the panel. I am also fairly certian that the ICs/transistors that light the LEDs are good. I tested for voltage on the input pins of the ICs from the control and found none when there should have been some. To test the IC I jumpered 5V to the input pin for one of the LEDs (I know, risky to do) and the LED lit. I also called up the ladder program for the PLC and confirmed that the outputs for the LEDs I was focusing on where turning on.

I don't know where to check next. It was suggested in the electronics forum that maybe the outputs were disabled. I don't have all of the manuals/docs for the machine, but a couple that I have contain some parameter lists. I have scoured them and cannot find one that I can tell would turn off these outputs. But I may have missed it or lost it in the wonderful wording of the translations for the manuals.

Does anyone know of any parameter in the 10TF that would cause this? Or have any other idea what might be doing it? Maybe some other electronic component or baord that may be bad? I am open to any and all suggestions.

Sorry for the length of this post, I tend to get long winded and I wanted to give any detail that may come in handy to someone who can help. I also want to say thanks in advance for any thoughts and time considering/pondering my problem. At the very least I am sure I will learn from what anyone has to say and I try to suck up all the education I can get.

Best Wishes,
Rob