8.6 The hotbed or extruder can not be heated
http://www.geeetech.com/forum/viewtopic.php?f=13&t=17039
8.7 LCD error: MAX/MIN TEMP error
http://www.geeetech.com/forum/viewtopic.php?f=13&t=17030
8.8 No information or displaying black square on LCD
http://www.geeetech.com/forum/viewtopic.php?f=13&t=17040
8.9 Time.h/endstop hit or other abnormalities
http://www.geeetech.com/forum/viewtopic.php?f=13&t=17037