Power subsystem
Power-on checks
Turn on the power. If the control-panel display remains blank or if it displays random patterns or asterisks, perform the power-on checks to find the cause of the problem.
1.Verify that the product is plugged into an active electrical outlet that delivers the correct voltage.
2.Verify that the power switch is in the ON position.
3.Make sure that the main fan on the right side runs for a short time.
●If the control-panel display is blank, but the main fan runs after the power is turned on, print an engine test page to determine whether the problem is with the control-panel display, the formatter, or other components. See Engine diagnostics on page 134.
●The overcurrent/overvoltage protection circuit in the low-voltage power supply unit might be running. Turn the printer off, unplug the power cord, and turn the printer on. If the printer does not function, the fuse melts, or the power supply is malfunctioning, replace the engine controller unit. See Engine control unit (ECU) on page 110.
●Verify that the LEDs at the back of the product on the formatter, are functioning correctly. See LED diagnostics on page 133.
4.Remove any HP Jetdirect or other EIO cards, and then turn off and turn on the product.
132 Chapter 3 Solve problems | ENWW |