COPYRIGHT © 2001 CANON INC. 2000 2000 2000 2000 CANON iR8500/7200 REV.1 AUG. 2001CHAPTER 6 TROUBLESHOOTING6-1454.1.91 The drum heater fails to operate----------1) Open the front cover, and release the fixing/feeding assembly. Arethe ends of the drum warm? (Do not touch the drum.)YES: The drum heater operates.DC controller PCB2) Set the meter range to 12 VDC. Connect the meter probes to J505-A7 (+) and -A8 (−−−−−) on the DC controller PCB. Is the voltage be-tween the terminals 5 V in standby?NO: Replace the DC controller PCB.AC drive PCB3) Try replacing the AC driver PCB. Is the problem corrected?YES: End.Drum heater (H3), Drum heater controller PCB4) Remove the drum. Set the meter range to Ω×Ω×Ω×Ω×Ω×1, and connect themeter probes across the terminals of the heater. Does the index ofthe meter swing?NO: Replace the drum heater.YES: Replace the drum heater controller PCB.4.1.92 The “Add Toner” message fails to turn ON----------1) Is there toner inside the hopper?YES: Go to step 2).Toner sensor (hopper assembly), DC controller PCB, DC controller, Control panel2) Make the following selections in service mode: COPIER>I/O>DC-CON. Then, move aside toner to expose the toner sensor (TS1). Atthis time, does bit 0 of P003 indicate ‘0’ (absence of toner)?NO: Perform the following:1. Replace TS1.2. Replace the DC controller PCB.YES: Perform the following:1. Replace the DC controller PCB.2. Replace the control panel.
