37. The vertical path roller fails to rotate.38. The registration roller fails to rotate.COPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)CHAPTER 11 TROUBLESHOOTING11-107CauseBelt, Gear,CouplingRegistrationpaper sensor(PS23)Registrationroller driveclutch (CL9)DC controllerPCBChecksIs the drive from the main motor(M1) transmitted to the registrationroller through the belt, gear, andcoupling?Is the registration paper sensor(PS23) normal?Connect the – probe of the meterto GND and the + probe to J108A-5. Does the voltage change fromabout 24 to 0 V as soon as theregistration roller starts to rotate?Step123YES/NONONOYESNOActionInstall the belt, gear, andcoupling correctly.Replace the sensor(PS23).Replace the clutch(CL9).Replace the DCcontroller PCB.CauseBelt, Gear,CouplingVertical pathroller clutchDC controllerPCBChecksIs the drive from the pick-up motor(M2) transmitted to each verticalpath roller through the belt, gear,and coupling?Connect the – probe of the testerto GND and the + probe to the ter-minal indicated. Does the voltagechange from about 24 to 0 V assoon as the roller starts to rotate?Vertical path 0 drive clutch (CL18) J115A-4Vertical path 1 drive clutch (CL15) J117A-15Vertical path 2 drive clutch (CL17) J121B-8Vertical path 3 drive clutch (CL11) J117B-2Vertical path 4 drive clutch (CL13) J130B-2Step12YES/NONOYESNOActionInstall the belt, gear, andcoupling correctly.Replace the appropriateclutch.Replace the DCcontroller PCB.Download service manual and resetter printer at http://printer1.blogspot.com