Bizhub 361 Trouble Code C-3502/ C-3801

[MFPTech]

Rebuilt a fuser from another machine (same model), and came to replace it but I am getting C-3502 C-3801 trouble codes.
Repositioned thermostat and thermistors, could not find anything wrong on the rebuilt unit. Reset the Fixing counter, no go. Sometimes I might get a print out and it errors again ... it looks like the machine does not like this unit ... Am I missing something?

Thanks in advance!

[jotunn]

Re: Bizhub 361 Trouble Code C-3502/ C-3801

Are you sure it wasn't fixing unit (especially fixing roller upper) from Bizhub 500/501?

Fixing roller wall thickness differs between 361/421 and 501 - it changes thermal capacity of fixing roller, and once it seems too cold for the engine then too warm.