Assuming the 3 leds are dead (for whatever reason) does the machine have any life?
Forgot to add.....when you measure the voltages on the chips etc, do you have the negative lead on a common ground point somewhere on the board?
It's preferable to measure the volts (and ground) on the chip pins to prove 5v/0v is actually arriving at the chip.
There can always been a broken ground-track between the common board ground and the chip-pin....
May be go re-measure your chips?
MM.