HP LaserJet 5000 Service Manual - Page 228

Power On It is important to have the printer's Control Panel functional as soon as possible in the troubleshooting process so that the printer's diagnostics can assist in locating printing errors. Table 7-2. Power on Defect or Blank Display Problem Action Is the power cord plugged into the wall and the printer? Is AC and DC power available? Verify. See table 7-3, "No AC Power," on page 7-8 and table 7-4, "No DC Power," on page 7-9. Is the power switch set to on? Set the switch to the on position. You should hear the switch toggle. If the Front Right Side Cover has been removed recently, be sure that the rod leading to the power supply moves as the rocker switch is toggled. Does the Fan turn on when Note: Fan operation is significant since the Fan is controlled by you turn on the printer? the printer's Engine Controller Board. An operational Fan indicates the following: 1. AC power is present in the printer. 2. DC power supply is functional (24 VDC, 5 VDC, and 3.4 VDC are being generated). If the Fan is not working: 1. Turn off the printer and remove the printer's Formatter PCA. Disconnect all the printer's paper handling options. 2. Turn on the printer and check the Fan again. If the Fan is still not working, perform the following steps: 1. Verify that the Fan is connected to the DC Controller Assembly. 2. Replace the Fan. 3. Replace the Power Supply. If the Fan is working but the printer's Control Panel is blank: 1. Print an engine test. See "Engine Test" on page 7-9. If the engine test is successful, perform the following steps: a. Reseat the Control Panel and Formatter connector. b. Replace the Control Panel assembly. c. Replace the Formatter. d. Replace the cable from the Control Panel. 2. If the engine test is not successful, replace the Power Supply. EN Troubleshooting the Printing System 7-7