Steven,
I would, in this case, advise an engineer that is familiar with the appliance as, if you search through the forums you will see that “E2” indicates another problem and is more often sorted without the timer being replaced.
However, the soap dispencer problem could well indicate a timer failure.
You will also find, in the forums, the reset procedure on several posts. There is no configuration to be done at all, just install, reset and it should work assuming that there are no other issues.
Pop up your postcode or have a look in the directories as there are quite a few of here that service Diplomat machines.
K.