Geeetech

Hi! The display of bed temperature is always on 70 degrees and the bed is off,cold.I can't set the temperature on 60,for example. Why? Thank you very much!

Hi，is it impossible to heat? What is the temperature of the hotbed when not heating?

Hi!
Th temperature of hotend is ok. I put new termistor.Maybe is 5 degrees higher.But i can control it.
p.s is it possible to heat but only if a set the temperature at 72 degrees (on display 70/72).And the heat goes to max.

Hi, you should check the connection. May be caused by poor contact.
and then,you can Unplug the cable of the extruder.
If the extruder shows a temperature of -14°C, the motherboard is good. If not, the motherboard is broken.
You can also use a multimeter to test the continuity of the cable to see if the cable is damaged.

Hi!
Yes. If i unplugged the termistor the temperature is -14.But the problem is not the extruder temperature. The problem is the BED temperature. On display is always 70 or 71. If i unplugged the cable ob motherboard notjng changes. See the picture in attachment. Thank you

Nothing happens if i unplugged the cable.

Hi，if it is a hotbed problem, you can unplug the connection between the hotbed and the motherboard to see if the hotbed shows -14 ℃, if it shows, the motherboard is good.
Then it may be caused by the opening of the thermal bed thermistor. You can measure whether the resistance of the thermistor is about 80-120 kilohms, or the line of the thermal bed is broken.

Hi!
If i unplugged the termistor the temperature on display is always 70.

Hi，the motherboard is broken, you need to replace it.
You can contact the salesperson on the purchase platform