02/20002-28 DocuPrint N2125RAP 25Initial IssueStatus Indicator Repair Analysis ProceduresRAP 25 Malfunctioning LCD/LEDThere is an erratic display on LCD/LED.ProcedureSwitch the printer power off. Remove any options connected to the System Controller PWB.Disconnect P/J18 from the System Controller PWB. Switch the printer power on. On the Sys-tem Controller PWB, check the following voltages between P/J18 and frame ground.All the voltages listed in the column “with P/J18 disconnected” are correct.Y NOn the System Controller PWB, check the voltage on P/J13 between pins 1 and 2. Thevoltage is 3.3VDC.Y NSwitch the printer power off. Disconnect P/J13 from the System Controller PWB.Switch the printer power on. Check the voltage between pins 1 and 2 on the discon-nected plug. The voltage is 3.3VDC.Y NOn the LVPS, check the voltage on P/J282 between pins 1 and 2. The voltageis 3.3VDC.Y NReplace the LVPS (REP 9.5).Repair or replace the harness between the LVPS and the System ControllerPWB (PL 10.1).Replace the System Controller PWB (REP 9.2).On the System Controller PWB, check the voltage on P/J13 between pins 3 and 4. Thevoltage is 5.0VDC.Y NSwitch the printer power off. Disconnect P/J13 from the System Controller PWB.Switch the printer power on. Check the voltage between pins 3 and 4 on the discon-nected plug. The voltage is 5.0VDC.Y NOn the LVPS, check the voltage between P/J PN1 pins 1 and 2. The voltage is24.0VDC.Y NReplace the LVPS (REP 9.5).Replace the System Controller +5.0VDC Power Supply (REP 9.4).Replace the System Controller PWB (REP 9.2).Switch the printer power off. Reconnect P/J18 to the System Controller PWB. Switch theprinter power on. Check the voltages between the pins listed in Table 1 and frameground. All the voltages listed in the column “with P/J18 connected” are correct.Y NReplace the Control Panel Assembly (PL 1.1).Switch the printer power off. Reinstall the removed options one at a time, switching on thepower and checking the voltages between the pins listed in Table 1 and frame groundafter each component is installed. Replace the option just installed if the voltage fails.After all the options are reinstalled, the LCD display is still erratic.Y NProblem solved. Return to Initial Actions and restart.Replace the Control Panel Assembly (PL 1.1). If the problem persists, replace the SystemController PWB (REP 9.2).Switch the printer power off. Reconnect P/J18 to the System Controller PWB. Switch theprinter power on. Check the voltages between the pins listed in Table 1 and frame ground. Allthe voltages listed in the column “with P/J18 connected” are correct.Y NReplace the Control Panel Assembly (PL 1.1).Switch the printer power off. Reinstall the removed options one at a time, switching on thepower and checking the voltages between the pins listed in Table 1 and frame ground aftereach component is installed. Replace the option just installed if the voltage fails. After all theoptions are reinstalled, the LCD display is still erratic.Y NProblem solved. Return to Initial Actions and restart.Replace the Control Panel Assembly (PL 1.1). If the problem persists, replace the System Con-troller PWB (REP 9.2).Table 1P18With P/J18DisconnectedWith P/J18ConnectedPin 1 3.3VDC 3.3VDCPin 2 0.0VDC 0.0VDCPin 3 1.4VDC 3.3VDCPin 4 0.0VDC 0.0VDCPin 5 3.3VDC 3.3VDCPin 6 1.4VDC 3.3VDCPin 7 3.3VDC 3.3VDCPin 8 0.0VDC 3.3VDCAABBCC
