HP 3150 EN - Manual (Page 182)

180 Troubleshooting EN
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 76. Toner cartridge high-voltage connection points