What kind of DEC did you replaced? Did you use Galileo Dec or Avantra? How about the removable Ics ? Did you replace them? Could be the possible broken pins.
If you used the correct and reliable Galileo DEC, then the second consideration might be the cables connected to DEC and the carriage. Have you worked on the carriage and the flat cable connector? The flat cable must be connected to the right 4c pcb's slot.
I need to know how the red LED reacts to the power on sequence.
CONTROLLING THE PURSE STRINGS
By Noel Ward, Editor@Large
What did you buy for your business last week?
And how are you making sure everything you purchase is properly
managed and accounted for? Read the Article