301-13 help please

[leebo]

I have two 301-13s that seem to be almost dead--one reads all ffffs and the other reads all 0000s when read in wall. I've tried all of the procedures I could find for wall and jkeys and none work. one I can get to flash programming with trap functional but all grey in the address areas. I've done two 013 single and one 010 dual and they work great but these two have me stumped. There are no obvious signs of physical damage to the components. I'd like to do some trouble shooting if someone will help me with the test points and the values to look for.
Thanks to all.

[leebo]

Come on experts have you NO mercy???

[lefty]

Come on experts have you NO mercy???

I have never had to use Wall to bring one back to life. I've been pretty lucky so far.

Are any of the chips getting real hot?

[leebo]

Thanks for the response. Nothing seems to be getting hotter than normal, I may have grounded the wrong side of r79 on this one, if so, what does it burn?

[JT]

You ground the right side of R79. (which is the left side if your looking at the board from the front still in the case) Right or left is determined by the lable.

[leebo]

I know that but thanks, you missed the question--What happens if you ground the wrong side??