3–133OPERATIONS AND TIMINGCOPYRIGHT © 1998 CANON INC. CANON NP6621 REV.0 FEB. 1998 PRINTED IN JAPAN (IMPRIME AU JAPON)6 Initializing the Back-Up RAM1) Open the front door, and insert the door switchactuator into the door switch.2) Press the service mode switch (SW850) with ahex key.• The machine enters service mode and indi-cates ‘1’.3) Press ‘4’ on the numeric keypad.• The display indicates ‘4’.4) Press the AE key.• The machine starts operation/inspection modeand indicates ‘401’.5) Press ‘5’ and ‘0’ on the numeric keypad.• The display indicates ‘450’.6) Press the Start key.• The display changes to ‘EE’.8) Press the Start key.• The display returns to ‘EE’.9) Turn OFF/ON the power switch.• The back-up RAM is initialized and set todefault settings.Reference:To stop initializing the RAM, press the Clear keyand then the Reset key.To stop it after performing step 8), press thestart key, and press the Start key after thedisplay has indicated ‘nop’.7 Checking the PhotointerruptersThe machine’s photointerrupters may bechecked using a conventional meter or in servicemode.q Using a Meter1) Set the meter to the 12VDC range.2) Connect the - probe of the tester to J301-4(GND) of the DC controller.3) Make checks as indicated.1: 5 V0: 0 Vw Using Service Mode1) Open the front door, and insert the doorswitch actuator into the door switch.2) Press the service mode switch (SW850)with a hex key.3) Press ‘2’ on the numeric keypad.• The display indicates ‘2’.4) Press the AE key.• The machine enters I/O display modeand indicates ‘201’.5) Enter the appropriate number using thenumeric key, and press the Start key.• Check each photointerrupter with refer-ence to the copy count indicator.Figure 3-8012-a 1-a2-f2-b2-g2-e2-c2-d1-f1-g1-b1-e1-d1-c
