blackout control panel LCD

[theo]

hi,

one machine of my boss has big problem. it is canon iR8500. the control panel LCD has black out and the keypad not working.

yesterday morning we used that machine for printing some papers. after 12 oclo'ck shut off. when back to work at 4 p.m.,pressing ON by the operator the machine doesn't work.

i checked the machine, removing the panel board assembly locating if theres short...but i did not found any.

if you swicth on the side ON and OFF switch at the side ONLY THE the green LED light on the panel. which i think connected to the main switch. the rest lcd, keypad and on and off switch for standby mode not working its dead on the panel.


do u have any trouble like this? i called to local canon here, they said the trouble is new have also same trouble at the thier shop which need for troubleshooting (not yet sure which parts is defective).


can u tell me which possible circuit is damage? why its happen suddenly? u cannot see error code because theres no lcd display.


please help me. thanks

[_SuabE_]

I had this problem yr 2002, Do this dismantle the Main Power supply PCB locate a small step down transformer. The function of this xformer is for standby power on you can see it near the corner of the PCB. The primary winding of this xformer is open due to electrical problem. Pa rewind mo lang yun.

[rambo40]

hi,

one machine of my boss has big problem. it is canon iR8500. the control panel LCD has black out and the keypad not working.

yesterday morning we used that machine for printing some papers. after 12 oclo'ck shut off. when back to work at 4 p.m.,pressing ON by the operator the machine doesn't work.

i checked the machine, removing the panel board assembly locating if theres short...but i did not found any.

if you swicth on the side ON and OFF switch at the side ONLY THE the green LED light on the panel. which i think connected to the main switch. the rest lcd, keypad and on and off switch for standby mode not working its dead on the panel.


do u have any trouble like this? i called to local canon here, they said the trouble is new have also same trouble at the thier shop which need for troubleshooting (not yet sure which parts is defective).


can u tell me which possible circuit is damage? why its happen suddenly? u cannot see error code because theres no lcd display.


please help me. thanks

Hi,

You either have a problem with the ALL NIGHT/DAT Power supply PCB.or the BOOT ROM.Reseat the boot rom if no go then check the power supply for output voltage.This power supply sits on the LHS above the main power supply.I think the part number is FG6-7268