Reverting From MK3/MMU2 back to MK3 Problems
I have a few i3 printers at work and one of our MK3 units was upgraded to have an MMU2 as well. Unfortunately in our environment I don't have enough time to really get the MMU working correctly and it was really just down all the time. To get the printer back I tried to revert the printer back to a standard MK3 (Basically just undid the MMU2 kit extruder work, removed the MMU from the gantry, unplugged it, and flashed the standard MK3 firmware to the printer). The problem now is that the extruder won't heat, one person claimed it heated partially the first time they fired it up after the work was complete but I haven't seen it heat passed ambient yet. Originally I suspected the heater cartridge had just been damaged during assembly and I replaced the entire hotend, but the problem remained (Did this twice just to make sure I didn't have a bad heater cartridge/thermistor). I put checked to make sure the heater was getting power from the motherboard by checking voltage at the board, and found no power being sent from the board, which appears to be a bad motherboard. I don't quite think this is the case because the hotend was working fine before the un-conversion but I can't figure out whats going on. Has anyone else run into this problem before? Any advice would be greatly appreciated.
RE: Reverting From MK3/MMU2 back to MK3 Problems
While removing the MMU cables from the controller did you knock something else loose?
You keep referring to MK3, but it is important to know if we are really talking about an MK3S (IR sensor). You actually didn't need to flash the printer after uninstalling the MMU, but since you did make sure that you flashed the correct version (e.g. MK3 or MK3S). I don't see how the differences between the 3 and 3S would cause a heating problem though.
You mentioned checking and replacing the heater, did you check/replace the thermoresistor as well? It's wires can get broken just as easily. I would expect the printer to throw errors, however, if either the heater was working and it wasn't getting expected results from the thermo or if the thermo was working and not seeing a temp change from the heater.
RE: Reverting From MK3/MMU2 back to MK3 Problems
Sounds to me like wrong firmware was flashed. You should measure 24V on the heater rails once preheat is started (and no error message is appearing)
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RE: Reverting From MK3/MMU2 back to MK3 Problems
I replaced the entire hotend (heater cartridge, thermistor, metallic parts) and the thermistor is reading the same ambient temp as the bed thermistor and isn't throwing any problem codes. I checked and reflash the firmware twice to make sure I wasn't messing something up. Just to be sure, I flashed this file: "prusa3d_fw_MK3_3_8_1_2869.hex" from prusa3d.com.
RE: Reverting From MK3/MMU2 back to MK3 Problems
I replaced the entire hotend (heater cartridge, thermistor, metallic parts) and the thermistor is reading the same ambient temp as the bed thermistor and isn't throwing any problem codes. I checked and reflash the firmware twice to make sure I wasn't messing something up. Just to be sure, I flashed this file: "prusa3d_fw_MK3_3_8_1_2869.hex" from prusa3d.com.
Do you have the IR sensor or did you revert all the way back to the laser sensor? If you have the IR sensor installed then you installed the wrong firmware and you need the MK3S version.
RE: Reverting From MK3/MMU2 back to MK3 Problems
Just tried flashing MK3S firmware to it to see if I had missed something. Same problem, looks like replacing the board is the next logical step.
RE: Reverting From MK3/MMU2 back to MK3 Problems
I replaced the entire hotend (heater cartridge, thermistor, metallic parts) and the thermistor is reading the same ambient temp as the bed thermistor and isn't throwing any problem codes. I checked and reflash the firmware twice to make sure I wasn't messing something up. Just to be sure, I flashed this file: "prusa3d_fw_MK3_3_8_1_2869.hex" from prusa3d.com.
Do you have the IR sensor or did you revert all the way back to the laser sensor? If you have the IR sensor installed then you installed the wrong firmware and you need the MK3S version.
Sorry I replied without refreshing and didn't see this. No the IR sensor isn't installed, it's completely reverted.