4-58 Phaser 4500/4510 Service ManualGeneral TroubleshootingStacker Rear Cover SwitchTroubleshooting ReferenceApplicable Parts Wiring and Plug/Jack Map References■ Rear cover switch■ Rear cover assembly harness■ Stacker PWBA■ Stacker harness 2■ HVPS/engine logic board■ LVPS■ Stacker harness 1■ “Stacker Signal Diagram” on page 10-37■ “Stacker General Wiring Diagram” onpage 10-36■ “P4500: 24 V Interlock, Rear Cover Switch,Main Motor, Sub Fan, Exit Motor Assembly” onpage 10-21■ “Stacker Plug/Jack Locator” on page 10-16Troubleshooting ProcedureSteps Actions and Questions Yes No1 Check the rear cover switch (1):1. Remove the rear cover switch.2. Test for continuity across J740-2 <=>J740-1 while pushing and releasing thestacker rear cover switch.Is the switch continuous when pushed,and open when released?Go to step 2. Replace therear coverswitch.2 Check the rear cover harness:1. Remove the rear cover harness.2. Test J74 <=> J740 for continuity.Is the harness continuous?Go to step 3. Replace therear coverharness.3 Check stacker harness 2:1. Disconnect P/J70 from stacker PWBA.2. Remove stacker harness 2.3. Test J70 <=> J3070 for continuityIs the harness continuous?Go to step 4. Replacestackerharness 2.4 Check stacker harness 1:1. Remove stacker harness 1.2. Test J30 <=> J3070 for continuityIs the harness continuous?Go to step 5. Replacestackerharness 1.5 Check the rear cover switch (2):Measure the voltage across P/J30-4 <=> P/J30-3 on the HVPS/engine logic board.Does the voltage measure +3.3 VDC?Go to“StackerPWBA” onpage 4-54.Go to step 6.6 Check the HVPS/engine logic board:1. Disconnect P/J30 from the HVPS/enginelogic board.2. Test P30-4 <=> P11-16 for continuity.Is it continuous?Replace theHVPS/enginelogic board(page 8-73).Go to “LVPS(Low VoltagePowerSupply)” onpage 4-4.
