Phaser 4400 Laser Printer Service Manual 2-45Main Motor Failure.(U1 Motor Fail/Power Off)Main Motor speed is less than specified RPM after 1.3 seconds.There is a problem with the Main Motor.16 1. Remove Tray 2 from the feeder.2. Check the voltage between the lower terminal on theFeeder Connector and frame ground.Is the voltage +24 VDC?Go to step18.Go to step17.17 Check the wiring harness between the Tray 1 SizePWB (P/J51) and the Tray 2 Size PWB (P/J52).Is the harness in good condition?Replace theTray 2 SizePWB (RRP11.19 onpage 6-139)then the Tray2 FeederPWB (RRP11.9 onpage 6-128).Replace theSize HarnessAssembly(PL 11.1 onpage 7-27).18 Replace the following components, in order, until theproblem is resolved: Stack Height Sensor (RRP 11.13 on page 6-132) Feeder PWB (RRP 11.9 on page 6-128) Size PWB (RRP 11.19 on page 6-139) Engine Logic Board (RRP 9.3 on page 6-89)19 Remove the tray now occupying the Tray 1 positionand continue with Tray Motor Assembly Checkout onpage 3-26.Main Motor Failure Troubleshooting ProcedureStep Actions and Questions Yes No1 1. Switch the printer power OFF.2. Remove the Left Interface Cover (RRP 1.1 onpage 6-6), the Left Cover (RRP 1.2 on page 6-7), andthe Left Plate (RRP 1.11 on page 6-16).3. Open the Rear Cover and, if installed, remove theDuplex Unit.4. Manually rotate the rotor of the Main Motor clockwise(as viewed from the left side of the printer).Does the rotor of the Main Motor rotatesmoothly?Go to step 5. Go to step 2.2 1. Open the Front Cover and remove Print Cartridge.2. Manually rotate the rotor of motor clockwise.Does the rotor of the Main Motor rotatesmoothly?Replace thePrintCartridge.Go to step 3.Tray Failure Troubleshooting Procedure (cont'd.)Step Actions and Questions Yes No
