If anyone has found a way to repair or replace the mirror, I hope they will share the knowledge.

The two mirror mounting lugs appear to be glued to the aluminium beam that forms the backbone of the projector optical system, and I am not sure how to adjust the screws that set the angle of the mirror. When I have a projector with a damaged mirror I strip it down for parts to repair projectors with other faults.

Thank you, Shane. It is nice to know the guide is appreciated. I wrote the guide when I was quoted £800 to repair one of our school projectors. Instead of paying I started buying second hand projectors, so I had nothing to lose from cannibalising the broken ones. Writing a guide helped me record the details to ensure I could put them back together!

With practice it gets easier to remove the case. They are quite strong. After removing ALL the screws I just pull hard at the opening for the bulb and I have not yet broken a case. Just remember to also remove the two screws hidden under the bulb cover.

David

Michael, this guide is for a full projector disassembly. The simpler task of replacing a faulty DMD chip is covered in a separate guide.

The Lexmark C780 fuser is different from the fuser I described in this guide. I have never dismantled one or seen a guide.

The C780 service manual offers a very large range of error causes: Error code 122.01 indicates that the fuser heated up too quickly or not quickly enough. Error code 122.01 may also indicate a problem in the fuser assembly with the hot roll bearings, hot roll thermistor, LVPS, or the system board. ... If error code 122.08 displays, the printer has detected a problem in the fuser hot roll lamp circuity, fuser hot roll thermistor, system board, or LVPS fuser control circuits.

I would start by checking the heated lamp is not open circuit. There might also be a safety device near the hot roller that melts to break the circuit if the fuser overheats. I once found such a device had failed open circuit. Beyond those two suggestions the printer is too far outside my experience for me to help you further.

David Co

I cannot suggest why you would get an error code 122.01 or 122.08. That error code is not listed in the service manual.

I do not understand why you say the lamp goes inside the orange roller. On all the Lexmark T650 fusers I have seen, the roller with the heater lamp inside is grey or dark blue. This sits above the solid orange pressure roller. It would be impossible to put a lamp inside the solid orange pressure roller. On the pictures in the guide, the heater lamp goes inside the grey roller.

I think David Co is asking why the wedges are needed. The strong springs pull the two rollers together hard. The wedges lift the springs which separates the two rollers. This serves two purposes:

a) It would not be possible to remove the rollers while they were still under pressure from the springs.

b) When the fuser is in storage the wedges prevent the springs making a flat spot where the two rollers are pulled together.

You could unhook the springs instead of making wedges.

When the fuser is in the printer, the printer wakes up and rotates all its rollers every few minutes which prevents flat spots forming.

The documents I have found suggest that the DMD chips are not compatible. Here is a list of projectors that are compatible with the UF75 DMD chip: https://www.replaceyourlamp.co.uk/projec... and a different list of projectors compatible with the UF55 DMD chip: https://www.replaceyourlamp.co.uk/projec...

The lamps are different: the UF75 lamp is 230 watt but the UF65 lamp is 200 watt and the housings look slightly different.

I don’t know about the colour wheel compatibility.