Troubleshooting 3 - 81Verifying print engine operation by printing a builtin page.1. If not already on, turn on the printer. If the printer does not begin initializing, go to thetopic, ìMeasuring power supply voltagesî.2. Once the Power light is on (not blinking) and the front panel displays Ready toPrint it is now possible to print any built-in pages.3. If the printer prints the Page, the print engine is working correctly. If the printer doesnot print the Page, then a problem exists with the print engine.Verifying power supply operationThe power supply is divided into two sections: the AC section used for heaters and theDC section for control logic, printhead drivers and motors. Verifying the power supplyinvolves three steps: Checking for proper AC voltage. Inspecting the power supply fuses. Testing for a shorted motor or solenoid driver, which shuts down the powersupply. See SF 156 ( Phaser 840 only).Measuring power supply voltagesWarning AC line voltages are present on the power supply and possibly inthe printer, via the heaters, while the printer is plugged into an ACoutlet, even if the power switch is off.1. Turn off the printer and unplug it from its power outlet.2. AC Input: With a DMM set to measure AC voltages, measure the power beingsupplied to the printer; it should measure between 87 to 128 VAC (115 VAC nominal)or 174 to 250 VAC (220 VAC nominal).3. Proceed to the step, ìInspecting the power supply fusesî below.If a heater shorts, F2 or F3 opens. The power supply does NOT shut down;however, a Service Required error code is displayed on the front panel.Required tools TORX T-20 screwdriver Digital multi-meter (DMM)
