mxm450 mother board

[bonnie750]

Had a problem today on a mxm450. original fault was jamming/not feeding from tray1. i stripped the gearbox, changed the feed clutch and rebuilt the m/c. it came to ready and fed from tray 1 perfectly but copies were blank. switch off, check wiring etc, switch on........nothing, well almost. there was a led on the pcu pwb and after 15 secs the fans at the exit ran then stopped.

none of the usual fuses blown and all connections ok. after a bit of digging i checked the 800ma fuse on the mother board which was gone.

my question is what is the function of the mother board and has anyone out there had any problems with it? tucked away out of sight it was pure luck i spotted it. i've no idea why that fuse had blown and i can't see any reference to the fuse in the service manual.

thanks

bill

[Silvertoast]

the mother brd is a interconnect between the control brd and the pcu brd. i have had to replace a couple of them and there a pita.