Hot end doesn't heat - solved

melodic · April 24, 2014

Starting up my newly assembled Ultimaker Original for its first run, the UltiController displayed a 'MAXTEMP' error and the nozzle didn't heat.

I already double checked all wirings and connections, looked on the forums here for some help.

The blower in the bottom of the printer works fine, as do the stepper motors X, Y Z and their stop ends.

So that part of the printer seems to work well.

I also tried to turn the heater in the nozzle on by hand using the UltiController (CONTROL > TEMPERATURE>NOZZLE). But it didn't respond.

I must admit that I'm not familiar with electronics so I'm stuck and need some help.

Can somebody give a hint which part to test next?

I would be grateful.

illuminarti · April 24, 2014

Check the wiring and connections again. There's a spare wire pair that runs from the head to the electronics. Try swapping over to that one for the temp sensor, and see if that makes a difference.

gr5 · April 24, 2014

The output at the top of the print head has a 3 pin connector which consists of ground (zero volts), power (5v I think) and a signal. The signal is 0v for 0C and 5V for 500C. So at room temperature it should read around 20C or 200mv.

If this signal is correct at the top of the UM, test it at the PCB. If it is correct at the PCB then there is probably a bad solder joint that connects that signal to the arduino - just reheat both ends of the circuit.

But more likely it seems you connect the wrong spare cable - the two cables are identical other than wire color.

Where to get circuit diagram:

ULTIMAKER1

The circuit diagram, and board layout are here:

http://reprap.org/wiki/Ultimaker%27s_v1.5.7_PCB

There is a zip file at the top. It contains the "brd" file which is the layout. Also the "sch" file which is the schematic.

Both files can be opened by eagle software which is free:

http://www.cadsoftusa.com/download-eagle/

ULTIMAKER 2 SCHEMATIC

https://github.com/Ultimaker/Ultimaker2