Canon BJC 6000 Service Manual - Page 116

Part 4: Technical Reference BJC-6000 5.1.8 Head temperature sensor Located inside the print head in the BJ cartridge, this sensor detects the head temperature so that the printer can stop printing when this sensor detects an abnormal temperature rise in the head as a head temperature abnormal error. The diode sensor output varying with the head temperature is detected as a varying voltage, so the incoming analog values are converted into digital values by the built-in A/D converter. 5.2 Other Detection Functions This printer features other detection capabilities as follows: 5.2.1 Waste ink amount detection Discharged ink from maintenance jetting to keep the print head in good working condition, and sucked ink as a result of cleaning is absorbed into the waste ink absorber. If more ink has been discharged than can be absorbed into the absorber, the ink may leak inside the printer. This waste ink amount detection function is provided to prevent ink leakage by estimating the waste ink absorber's capacity to absorb so that it can detect the ink-full condition. The printer calculates the amount of waste ink discharged by maintenance jetting and cleaning, based on the ink dot counter reading for the discharged ink, so that when the estimated waste ink volume reaches 95% of the waste ink absorber's capacity, allowing for evaporated ink, a waste ink warning will be issued on power-up. If this condition continues until the estimated waste ink amount reaches 100%, a "Waste Ink Full" error will be issued. 5.2.2 BJ cartridge detection The detection signals from the index unit, built into the print head heater board, detect the installed BY cartridges. For more, refer to Part 4: 3.2.3 d) Cartridge identification (Page 4-24). 4-44