COPYRIGHT © 2001 CANON INC. 2000 2000 2000 2000 CANON iR8500/7200 REV.1 AUG. 2001CHAPTER 6 TROUBLESHOOTING6-934 Troubleshooting Malfunctions4.1 Troubleshooting MalfunctionsIf you must remove and mount a sensor, pay attention to the orientation/po-sition of the spring used to lock its detecting lever in place while doing so.4.1.1 E000Thermistor1) Reset E000, and turn off and then on the power switch. Make thefollowing selections in service mode:COPIER>DISPLAY>ANALOG. Is overheating noted for both‘FIX-C’ and ‘FIX-E’?YES: The thermistor is faulty; check the following:• Thermistor for mounting condition• Thermistor surface for dirt• ConnectionDC controller PCB2) Turn offf the power switch, cooling the fixing upper roller suffi-ciently, and turn on the power switch. Reset E000, and turn off andthen on the power switch. Make the following selections in servicemode: COPIER>I/O>DC-CON. Are bit 0 and bit 1 of IO-P12 ‘0’?YES: Replace the DC controller PCB.Heater (open circuit), AC driver PCB3) Is the electrical continuity of each heater normal?NO: Replace the heater.YES: Check the wiring; if normal, replace the AC driver PCB.