120 Phaser 5400 Laser Printer Service GuideRAP 44 Inoperative PrinterPrinter power cannot be switched ON.Table 70 Inoperative Printer TroubleshootingStep Actions and Questions Yes No1 AC POWER CORDEnsure the power cord is properly connected to the walloutlet and to the back of the printer.Does the problem still exist?Go toStep 2.Problemsolved.2 AC POWERPerform RAP 38, AC Power, then return here.Did RAP 38 indicate the correct AC voltage isbeing supplied to the printer?Go toStep 3.Notifycustomerthat power isout of spec.3 DC POWERPerform RAP 40, DC Power (LVPS), then return here.Did RAP 40 indicate the correct DC voltages arebeing supplied throughout the printer?Go toStep 5.Go toStep 4.4 Did RAP 40 instruct you to replace acomponent?Replacecomponentasnecessary.PerformRAP 41,page 116.5 SYSTEM CONTROLLER +3.3 VDC CHECK1. Remove the Left Side Cover [RRP 1.1, page 250].2. On the System Controller Board, measure the voltagebetween P/J3-1 and P/J3-2.Does the voltage measure +3.3 VDC betweenP/J3-1 and P/J3-2?Go toStep 8.Go toStep 6.6 +3.3 VDC LOAD CHECK AT SYSTEMCONTROLLER P/J31. Switch printer power OFF.2. Disconnect P/J3 from the System Controller Board.3. Switch printer power ON.4. Check the voltage between pins 1 and 2 on thedisconnected plug.Is the voltage +3.3 VDC between pins 1 and 2 onthe disconnected plug?Go toStep 11.Go toStep 7.7 LOW VOLTAGE POWER SUPPLY1. Remove the Lower Rear Cover [RRP 1.7, page 256]to access the LVPS.2. Measure the voltage between P/J163-1 and P/J163-2.Note: Do not reinstall the Lower Rear Cover untilthis RAP is completed. You may need to makeadditional tests on the LVPS.Does the voltage between P/J163-1 and P/J163-2measure +3.3 VDC?Repair orreplace theharnessbetween theLVPS andthe SystemControllerBoard.Replace theLVPS[RRP 8.6,page 312].
