Problem with Z home

Hello,

I have a BQ Hephestos with a Zum Mega 3D. I put a heatbed and a bltouch and it always works perfectly.

1. This week I put the lead screw, changed the steps and Z Home stopped working correctly. When I do G28, X does the home, Y too, but the Z starts to rise up ...

2. After a few attempts to upload firmware, I turned off the EEPROM and started working correctly.

3. Yesterday I returned to send new firmware, only with changes in the digital potentiometer and the same problem happened again.

4. Today I went back to make new tests, reset the memory of the board and without knowing why the G28 returned to work well.

5. Then I changed the dupont plug of the bl_ouch's Z_Min, turned on the printer and climbed Z home again ...

Here is a video:

[youtu.be]

PS: Z only stops because I push the emergecy stop button in Pronterface.


I can not figure out where the problem is and I'm desperate for it. I think there are only two hypotheses: any problem on the firmware in board or bltouch Z_Min cable is damaged.

Does anyone know what it might be?

Edited 1 time(s). Last edit at 02/11/2017 08:48AM by jricardomiguel.

Hi guys,
frist of all, sorry for my bad english.

I need help, becuse i have same problem and no idea what can i do with my printer.

I bought a Geeetech auto bed level sensor (3D Touch) for my Geeetech Acrilyc i3 Pro B printer.

I used this manual, to install sensor:
http://www.geeetech.com/wiki/index.php/3DTouch_Auto_Leveling_Sensor#Firmware_Setting

I used firmware from here:
http://www.geeetech.com/forum/viewtopic.php?f=10&t=17046
5) Firmware for I3 pro&proB - I3 pro&proB(GT2560) Marlin-PI3_Pro_B.zip

I changed everything in config.h and pins.h and updated my printer with Arduino 1.01

The slef test and G-codes (below) works as well.

M280 P0 S10 ; pushes the pin down
M280 P0 S90 ; pulls the pin up
M280 P0 S120 ; Self test – keeps going until you do pin up/down or release alarm
M280 P0 S160 ; Release alarm

But, if i use on my printer (without PC) Prepare / Auto home option, X+Y home is ok, but Z home is not.
After XY home, the printer go XY center, and up about 5-10 mm, on every time.

I cant move down the the Z axis. (Just only if i reload the original firmware to the printer, and connecting back the original microswitch.)

Here is the video: https://youtu.be/cAtpjYk1S64

Thanks for all idea, if anybody have a working firmware, with working bed level sensor (3D touch) please uplad for me.

Thanks for all, and kind regards: Andras