Ricoh MPC2050 SC542

[Phil B.]

yes it came back with SC547
the fuser unit is not getting power form the power supply Board.

next time I would recommend getting your OHM meter and check continuity on each lamp... disconnect from the lamp contacts first...

then try the thermistors...
hold the thermostats in you hand for a min ( out of fuser ) then read with meter.

ANY open ..replace that part

[Phil B.]

Fuser does not attempt to warm up atll.
After I reset the sc code , it came up with SC547, whcih is pointing to power supply. There is no ourput power to the heaters of the fuser unit, looks like the relays are not commanded by the control unit to turn the heaters on. Do you know how the commands are generated to turn the power on to the heaters of the fuser unit?

look in SM.. Theory of Operation.. Fuser Section.. that will give you the path of the signals ..timing... and which part of the fuser requests power.

did you check for pinched/broken wires?

Start with backtracking your work ( after reading manual suggestion ) via disassembly
Perform the suggested check on components.
Check connection between fuser and machine.
reassemble and test