Power-on checks ............................................................................................. 132 Tools for troubleshooting .................................................................................................................. 133 Individual component diagnostics .................................................................................... 133 LED diagnostics .............................................................................................. 133 LED indicators ................................................................................ 133 Formatter heartbeat LED ................................................................
133 HP Jetdirect LEDs .......................................................................... 134 Engine diagnostics .......................................................................................... 134 Engine-test button .......................................................................... 134 Fuser test page ............................................................................................... 135 Paper-path test (and automatic sensors test) ................................................. 136 Sensor test (interactive) ..................................................................................
137 A TOP (Top-of-Page) sensor .......................................................... 140 B Fuser output sensor .................................................................... 141 C Duplex sensor ............................................................................. 142 D Paper width sensor 1 .................................................................. 143 E Tray 3 feed sensor ...................................................................... 144 F Tray 4 feed sensor ...................................................................... 145 G FD tray full sensor .......................................................................
146 H Face up detect sensor ................................................................ 147 I Cartridge-door open switch .......................................................... 148 J Rear cover open sensor .............................................................. 149 K Tray 1 paper sensor .................................................................... 150 L Tray 2 paper sensor .................................................................... 151 M Tray 2 detect switch .................................................................... 152 N Tray 3 paper sensor ....................................................................
153 O Tray 3 detect switch .................................................................... 154 P Tray 4 paper sensor .................................................................... 155 Q Tray 4 detect switch .................................................................... 156 Print/stop test .................................................................................................. 157 Component tests ............................................................................................. 158 Half self-test ....................................................................................
158 Drum rotation test check ................................................................. 158 Diagnostics menu components test ................................................ 158 Diagrams ......................................................................................................................... 160 Block diagrams ................................................................................................ 160 Plug/jack locations .......................................................................................... 162 Location of connectors ....................................................................................
163 ECU controller connections ............................................................ 163 Locations of major components ...................................................................... 165 General timing charts ...................................................................................... 169 General circuit diagram ................................................................................... 170 Internal print quality test pages ........................................................................................ 171 Cleaning page ................................................................................................. 172 viii ENWW