HP LaserJet 4 Service Manual - Page 443

service checkpoints 4-1, 4-3 Service Mode 3-20, B-25 service/error messages 3-59 setting the cold reset B-27 setting the page count 3-21, B-26 setting up the envelope feeder 3-50 settings, tray switch 5-9 sheet feeder installation 3-44 signals fan motor 5-10 main motor 5-10 Microswitch 5-8 Photosensor 5-6 scanner motor 5-10 solenoid 5-5 site requirements 2-1 Skip demo B-28 SL1, PC pick-up roller clutch solenoid 5-5 SL2, MP pick-up roller clutch solenoid 5-5 SL3 lower cassette pickup roller clutch solenoid 5-5 SLI (serial data in) 5-4 SLO (serial data out) 5-4 smeared print/improper fusing 7-35, 7-42 software B-35 shipped with printer B-34 solenoids 5-5 signals 5-5 space requirements 2-2 specifications IrDA B-34 labels 2-3, 2-5 paper 2-3 print media 2-3 standard printer operation 5-33 standby period 5-37 state machines 5-4 statement, RFI 1-9 station drum cleaning 5-18 drum conditioning 5-19 drum developing 5-22 drum transferring 5-24 drum writing 5-20 fusing 5-25 Status message troubleshooting 7-2 status, self test 3-26 sw601 7-19 sw601, top cover open sensor switch 5-8 sw602, test print switch 5-8 SW603 7-15 PC size switch 5-8 SW604 7-15 PC size switch 5-8 SW605 7-15 PC size switch 5-8 sw851, lower cassette size switch 5-8 sw852, lower cassette size switch 5-8 sw853, lower cassette size switch 5-8 switch locations 7-62 switch settings, paper tray 5-9 system communication 3-31 configuration 3-31 paper feed 5-26 T TB201 (voltage test points) 7-69 technical assistance 1-12 test menu B-24 test message for communications check 7-52 test print button 3-29 test print printout 3-29 test tool infrared B-39 thermistor removal 6-56 thermoswitch removal 6-55 timing 5-2 timing diagrams 5-34 toner cleaning 1-11 distribution 4-10 level 5-2 safety 1-11 toner cartridge 4-1, 4-5, 4-10 components 7-26 life 4-5 life expectancy 4-2 recycling 4-7 refilled 4-9 shelf life 4-6 storage 4-6 TONER LOW 4-10, 7-C message 7-25 TONER LOW=OFF 4-10 TONER LOW=ON 4-10 tools, required 6-2 top cover removal 6-5 trailing edge sensor PS5 7-44 transfer roller PM 4-3 removal and replacement 4-15 - 4-16 replacement 4-16 transferring station, drum 5-24 TRAY 1/2/3 LOAD message 7-13 Tray 2 tray size switches 7-15 TRAY 2/3 EMPTY 7-C TRAY X LOAD 7-C tray, switch settings 5-9 troubleshooting aids 7-59 Attendance messages 7-2 Index-7