Based on where the ink is leaking, I would look at the coupling between the ink line and the carriage. I would also say that it is probably a good idea to get HP service involved (800) 334-5144, based on the amount of ink that is leaking. The ink train is pressurized so any small leak will result in a significant amount of ink that escapes.
The fact that the printer is not reporting an error in the IPS means that the leak is small, but obviously a fair amount of ink is escaping. Liquid ink coming into physical contact with electronics tend to be a poor mix.