Re: indesit di 620
2 & 3 flashing is supposed to indicate a fill problem.
Sometimes removing the new module and inserting the old one before re inserting the new one can force a reset.
There are two different modules for this machine dependant on serial number. They are not interchangable.
Before serial number 6102.0000 it is a C00143206, after serial number 6102.0001 it is a C00143222.
Also worth checking the heating element for earth leakage as this can throw up spurious faults.
Jim.