This is just a “heads up” for Z users.
Sooner or later you will be faced with the error message “Reseat XX printhead”.
The web is full of complaints regarding people who have reseated the heads repeatedly with no result. Replacing the heads sometimes works.
Recently I was faced with a Reseat message that would not go away no matter how much I burnished the contacts or replaced heads, so in desperation I dug a bit further to check out the connection between the ribbon cable which contacts the printhead and the PCA board itself.
I found that the connector on the PCA board was loose and the connector clamp was in the “rolled down” not-clamping position. Re-inserting the ribbon cable and applying the clamp rectified the problem.
This carriage assembly had not been worked on previously and was either in that condition from the factory or else it had worked loose on its own.
This is a fairly drastic repair given the difficult of getting to the connector, but it is worth considering if all else fails.