Abstract: An inkjet printhead having a plurality of ink discharge nozzles that are served by respective ink supply conduits formed within a composite substrate includes ink discharge heaters respective to each of the nozzles, one or more substrate heaters for preheating an ink flow within the supply conduits and a plurality of resistors for monitoring the printhead quality during manufacture. The ink discharge heaters are in circuit with a first energy source connection and a common ground connection. The quality monitoring resistors are in series circuit with a second energy source connection and the common ground connection respective to the ink discharge heaters. At least one substrate heater is in circuit with a third energy source connection and the second energy source connection which, when the printhead is operatively connected for printing, is connected to ground.