After carefully removing the printhead in order to carry out a clean, on reinserting I get a message saying 'printhead not installed'. After re-seating the head 3 or 4 times the message is still the same. There is no apparent damage to either the multiway conacts on the back of the head, or the wiper type contacts on the carriage. likewise the multiway cable feeding the carriage looks good. How does the carriage 'sense' the presence of the printhead? Is it through the multiway contacts, or is there a 'proximity type' sensor somewhere in the head? I am reluctant to spend around £70-80 on a new print head without being able to prove that the fault lies within the head!