HP Color LaserJet Enterprise CM4540 Service Manual - Page 520

Distance between defects 55 mm 63 mm 76 mm 76 mm 80 mm 96 mm 101 mm Product components that cause the defect Print engine Transfer unit Print cartridge Fuser Fuser Print engine Print engine Calibrate the product Calibration is a product function that optimizes print quality. If you experience any image-quality problems, calibrate the product. 1. From Home screen, scroll to and touch the Device Maintenance button. 2. Touch the Calibrate/Cleaning button. 3. Touch the Full Calibration or the Quick Calibration button, and then touch the Start button. ● Full Calibration: takes about three minutes and performs color plane registration, drum speed adjustment, and Dmax and Dhalf adjustments. UseFull Calibration if colors are misaligned or appear blurry. Full Calibration runs automatically after a new transfer belt is installed. Full Calibration must be run manually after a laser scanner is replaced. ● Quick Calibration: takes approximately 1 minute and performs Dmax and Dhalf calibrations. Use Quick Calibration if colors are wrong, highlights are missing, or if colors are too dark or too light. Calibrate the scanner to compensate for offsets in the scanner imaging system (carriage head) for document feeder and flatbed scans. Because of mechanical tolerances, the scanner's carriage head might not read the position of the image accurately. During the calibration procedure, scanner offset values are calculated and stored. The offset values are then used when producing scans so that the correct portion of the document is captured. Scanner calibration should be carried out only if you notice offset problems with the scanned images. The scanner is calibrated before it leaves the factory. It needs to be calibrated again only rarely. Before calibrating the scanner, print the calibration target. 1. Place letter- or A4-size paper in Tray 1, and adjust the side guides. 2. From Home screen, scroll to and touch the Device Maintenance button. 3. Touch the Calibrate/Cleaning button. 4. Touch the Calibrate Scanner button. 5. Follow the steps displayed on the control panel to calibrate the scanner. 468 Chapter 3 Solve problems ENWW