Printer head goes to front left corner and stops  

Re: Printer head goes to front left corner and stops

It sounds as though the firmware is corrupted somehow. Did you recently update and accidentally install the wrong printer version, or has it corrupted itself by some means?

Head over to the shop and download and install the correct firmware for your printer, that should help.

https://www.prusa3d.com/drivers/#firmware

Re: Printer head goes to front left corner and stops

I did just replace the heating element and thermistor sensor in the hotend. No luck there and the same issue occurred. I uploaded the firmware again and no luck. I also sliced another simple model with Slic3r just in case it was the g.code. No luck.

I do see that after its first initial calibration point the temperature in the right of the / goes to 0 degrees for the bed and extruder. The SD% is also rather high at least 10% even though a print has not started.

I check connections and everything is solid on the board and bed and everywhere else. I do not think it is a thermistor since everything heats up and is fine until the middle of the calibration.

Could this be a power supply issue? Odd as everything does heat up and calibration starts. Seems to be something though that shuts off heating once the calibration is moving forward. Could it be the power supply is not providing enough power once the calibration starts moving the head around?

Now after messing around checking out the power supply (wiggling it) and checking that indeed the bed is getting power I find that the print head moves to print that first line upfront. Then exactly when the head goes upward the current to the bed is shut off and the bed moves forward to the back left corner. I restart and try to print again and it goes to the front left corner and fails before it extrudes that front first line.

Re: Printer head goes to front left corner and stops

It really does sound like a broken wire or intermittent short circuit. Try a preheat to PLA temperatures with the z-axis up at 100mm. See if it reaches and maintains temperature. Then move the bed cable bundle gently left to right and up/down and see if it goes off.

When the bed and nozzle are cold, remove the bed cable cover in the back corner and visually inspect the wire ends where they enter the solder.

Re: Printer head goes to front left corner and stops

Issue resolved - It was the bed thermistor. Works after replacing with one from Amazon Mmei 5pcs NTC 3950 100K Thermistor with 1 Meter Wiring and Female Pin Head for RepRap 3D Printer Extruder Heated Bed pre-wired or Hot End)

Then checked the old thermistor on the multimeter and another unit and it works fine. Odd as I vene retapped and positioned it before replacing. Oh, well. No harm. No foul and on to printing again.