High-voltage power supply check The high-voltage power supply PCA provides the necessary voltages for the electrophotographic processes. Checking the toner cartridge connection points Visually inspect the three connection points on the underside, right end of the toner cartridge: charging (callout 1), drum ground (callout 2), and developing roller (callout 3). If they are dirty or corroded, clean the connections, or, if they are damaged, replace the toner cartridge. Note Use only alcohol to clean the connections. Figure 71. Toner cartridge high-voltage connection points EN Functional checks 171 12 2 32